1.1.0.RC1
Copyright © 2013-2014
Table of Contents
This section provides a brief overview of Spring Boot reference documentation. Think of it as map for the rest of the document. You can read this reference guide in a linear fashion, or you can skip sections if something doesn’t interest you.
The Spring Boot reference guide is available as html, pdf and epub documents. The latest copy is available at http://docs.spring.io/spring-boot/docs/current/reference.
Copies of this document may be made for your own use and for distribution to others, provided that you do not charge any fee for such copies and further provided that each copy contains this Copyright Notice, whether distributed in print or electronically.
Having trouble with Spring Boot, We’d like to help!
spring-boot
.
Note | |
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All of Spring Boot is open source, including the documentation! If you find problems with the docs; or if you just want to improve them, please get involved. |
If you’re just getting started with Spring Boot, or Spring in general, this is the place to start!
Ready to actually start using Spring Boot? We’ve got you covered.
Need more details about Spring Boot’s core features? This is for you!
When you’re ready to push your Spring Boot application to production, we’ve got some tricks that you might like!
Lastly, we have a few topics for the more advanced user.
If you’re just getting started with Spring Boot, or Spring in general, this is the section for you! Here we answer the basic “what?”, “how?” and “why?” questions. You’ll find a gentle introduction to Spring Boot along with installation instructions. We’ll then build our first Spring Boot application, discussing some core principles as we go.
Spring Boot makes it easy to create stand-alone, production-grade Spring based Applications that you can “just run”. We take an opinionated view of the Spring platform and third-party libraries so you can get started with minimum fuss. Most Spring Boot applications need very little Spring configuration.
You can use Spring Boot to create Java applications that can be started using java -jar
or more traditional war deployments. We also provide a command line tool that runs
“spring scripts”.
Our primary goals are:
Spring Boot can be used with “classic” Java development tools or installed as a command line tool. Regardless, you will need Java SDK v1.6 or higher. You should check your current Java installation before you begin:
$ java -version
If you are new to Java development, or if you just want to experiment with Spring Boot you might want to try the Spring Boot CLI first, otherwise, read on for “classic” installation instructions.
Tip | |
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Although Spring Boot is compatible with Java 1.6, if possible, you should consider using the latest version of Java. |
You can use Spring Boot in the same way as any standard Java library. Simply include the
appropriate spring-boot-*.jar
files on your classpath. Spring Boot does not require
any special tools integration, so you can use any IDE or text editor; and there is
nothing special about a Spring Boot application, so you can run and debug as you would
any other Java program.
Although you could just copy Spring Boot jars, we generally recommend that you use a build tool that supports dependency management (such as Maven or Gradle).
Spring Boot is compatible with Apache Maven 3.0 or above. If you don’t already have Maven installed you can follow the instructions at http://maven.apache.org.
Tip | |
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On many operating systems Maven can be installed via a package manager. If you’re an
OSX Homebrew user try |
Spring Boot dependencies use the org.springframework.boot
groupId
. Typically your
Maven POM file will inherit from the spring-boot-starter-parent
project and declare
dependencies to one or more “Starter
POMs”. Spring Boot also provides an optional
Maven plugin to create
executable jars.
Here is a typical pom.xml
file:
<?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <groupId>com.example</groupId> <artifactId>myproject</artifactId> <version>0.0.1-SNAPSHOT</version> <!-- Inherit defaults from Spring Boot --> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>1.1.0.RC1</version> </parent> <!-- Add typical dependencies for a web application --> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> </dependencies> <!-- Package as an executable jar --> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> </plugins> </build> <!-- Add Spring repositories --> <!-- (you don't need this if you are using a .RELEASE version) --> <repositories> <repository> <id>spring-snapshots</id> <url>http://repo.spring.io/snapshot</url> <snapshots><enabled>true</enabled></snapshots> </repository> <repository> <id>spring-milestones</id> <url>http://repo.spring.io/milestone</url> </repository> </repositories> <pluginRepositories> <pluginRepository> <id>spring-snapshots</id> <url>http://repo.spring.io/snapshot</url> </pluginRepository> <pluginRepository> <id>spring-milestones</id> <url>http://repo.spring.io/milestone</url> </pluginRepository> </pluginRepositories> </project>
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The |
Spring Boot is compatible with Gradle 1.6 or above. If you don’t already have Gradle installed you can follow the instructions at http://www.gradle.org/.
Spring Boot dependencies can be declared using the org.springframework.boot
group
.
Typically your project will declare dependencies to one or more
“Starter POMs”. Spring Boot
provides a useful Gradle plugin
that can be used to simplify dependency declarations and to create executable jars.
Here is a typical build.gradle
file:
buildscript { repositories { mavenCentral() maven { url "http://repo.spring.io/snapshot" } maven { url "http://repo.spring.io/milestone" } } dependencies { classpath("org.springframework.boot:spring-boot-gradle-plugin:1.1.0.RC1") } } apply plugin: 'java' apply plugin: 'spring-boot' jar { baseName = 'myproject' version = '0.0.1-SNAPSHOT' } repositories { mavenCentral() maven { url "http://repo.spring.io/snapshot" } maven { url "http://repo.spring.io/milestone" } } dependencies { compile("org.springframework.boot:spring-boot-starter-web") testCompile("org.springframework.boot:spring-boot-starter-test") }
The Spring Boot CLI is a command line tool that can be used if you want to quickly prototype with Spring. It allows you to run Groovy scripts, which means that you have a familiar Java-like syntax, without so much boilerplate code.
You don’t need to use the CLI to work with Spring Boot but it’s definitely the quickest way to get a Spring application off the ground.
You can download the Spring CLI distribution from the Spring software repository:
Cutting edge snapshot distributions are also available.
Once downloaded, follow the INSTALL.txt
instructions from the unpacked archive. In summary: there is a spring
script
(spring.bat
for Windows) in a bin/
directory in the .zip
file, or alternatively you
can use java -jar
with the .jar
file (the script helps you to be sure that the
classpath is set correctly).
GVM (the Groovy Environment Manager) can be used for managing multiple versions of
various Groovy and Java binary packages, including Groovy itself and the Spring Boot CLI.
Get gvm
from http://gvmtool.net and install Spring Boot with
$ gvm install springboot $ spring --version Spring Boot v1.1.0.RC1
If you are developing features for the CLI and want easy access to the version you just built, follow these extra instructions.
$ gvm install springboot dev /path/to/spring-boot/spring-boot-cli/target/spring-boot-cli-1.1.0.RC1-bin/spring-1.1.0.RC1/ $ gvm use springboot dev $ spring --version Spring CLI v1.1.0.RC1
This will install a local instance of spring
called the dev
instance inside your gvm
repository. It points at your target build location, so every time you rebuild Spring
Boot, spring
will be up-to-date.
You can see it by doing this:
$ gvm ls springboot ================================================================================ Available Springboot Versions ================================================================================ > + dev * 1.1.0.RC1 ================================================================================ + - local version * - installed > - currently in use ================================================================================
If you are on a Mac and using Homebrew, all you need to do to install the Spring Boot CLI is:
$ brew tap pivotal/tap $ brew install springboot
Homebrew will install spring
to /usr/local/bin
.
Note | |
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If you don’t see the formula, your installation of brew might be out-of-date.
Just execute |
Spring Boot CLI ships with scripts that provide command completion for
BASH and
zsh shells. You can source
the script (also named
spring
) in any shell, or put it in your personal or system-wide bash completion
initialization. On a Debian system the system-wide scripts are in /shell-completion/bash
and all scripts in that directory are executed when a new shell starts. To run the script
manually, e.g. if you have installed using GVM
$ . ~/.gvm/springboot/current/shell-completion/bash/spring $ spring <HIT TAB HERE> grab help jar run test version
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If you install Spring Boot CLI using Homebrew, the command-line completion scripts are automatically registered with your shell. |
Here’s a really simple web application that you can use to test you installation. Create
a file called app.groovy
:
@RestController class ThisWillActuallyRun { @RequestMapping("/") String home() { "Hello World!" } }
Then simply run it from a shell:
$ spring run app.groovy
Note | |
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It will take some time when you first run the application as dependencies are downloaded, subsequent runs will be much quicker. |
Open http://localhost:8080 in your favorite web browser and you should see the following output:
Hello World!
Let’s develop a simple “Hello World!” web application in Java that highlights some of Spring Boot’s key features. We’ll use Maven to build this project since most IDEs support it.
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The spring.io web site contains many “Getting Started” guides that use Spring Boot. If you’re looking to solve a specific problem; check there first. |
Before we begin, open a terminal to check that you have valid versions of Java and Maven installed.
$ java -version java version "1.7.0_51" Java(TM) SE Runtime Environment (build 1.7.0_51-b13) Java HotSpot(TM) 64-Bit Server VM (build 24.51-b03, mixed mode)
$ mvn -v Apache Maven 3.1.1 (0728685237757ffbf44136acec0402957f723d9a; 2013-09-17 08:22:22-0700) Maven home: /Users/user/tools/apache-maven-3.1.1 Java version: 1.7.0_51, vendor: Oracle Corporation
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This sample needs to be created in its own folder. Subsequent instructions assume that you have created a suitable folder and that it is your “current directory”. |
We need to start by creating a Maven pom.xml
file. The pom.xml
is the recipe that
will be used to build your project. Open you favorite text editor and add the following:
<?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <groupId>com.example</groupId> <artifactId>myproject</artifactId> <version>0.0.1-SNAPSHOT</version> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>1.1.0.RC1</version> </parent> <!-- Additional lines to be added here... --> <!-- (you don't need this if you are using a .RELEASE version) --> <repositories> <repository> <id>spring-snapshots</id> <url>http://repo.spring.io/snapshot</url> <snapshots><enabled>true</enabled></snapshots> </repository> <repository> <id>spring-milestones</id> <url>http://repo.spring.io/milestone</url> </repository> </repositories> <pluginRepositories> <pluginRepository> <id>spring-snapshots</id> <url>http://repo.spring.io/snapshot</url> </pluginRepository> <pluginRepository> <id>spring-milestones</id> <url>http://repo.spring.io/milestone</url> </pluginRepository> </pluginRepositories> </project>
This should give you a working build, you can test it out by running mvn package
(you
can ignore the “jar will be empty - no content was marked for inclusion!” warning for
now).
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At this point you could import the project into an IDE (most modern Java IDE’s include built-in support for Maven). For simplicity, we will continue to use a plain text editor for this example. |
Spring Boot provides a number of “Starter POMs” that make easy to add jars to your
classpath. Our sample application has already used spring-boot-starter-parent
in the
parent
section of the POM. The spring-boot-starter-parent
is a special starter
that provides useful Maven defaults. It also provides a dependency-management
section
so that you can omit version
tags for “blessed” dependencies.
Other “Starter POMs” simply provide dependencies that you are likely to need when
developing a specific type of application. Since we are developing a web application, we
will add a spring-boot-starter-web
dependency — but before that, let’s look at what we
currently have.
$ mvn dependency:tree [INFO] com.example:myproject:jar:0.0.1-SNAPSHOT
The mvn dependency:tree
command prints tree representation of your project dependencies.
You can see that spring-boot-starter-parent
provides no
dependencies by itself. Let’s edit our pom.xml
and add the spring-boot-starter-web
dependency
just below the parent
section:
<dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> </dependencies>
If you run mvn dependency:tree
again, you will see that there are now a number of
additional dependencies, including the Tomcat web server and Spring Boot itself.
To finish our application we need to create a single Java file. Maven will compile sources
from src/main/java
by default so you need to create that folder structure, then add a
file named src/main/java/Example.java
:
import org.springframework.boot.*; import org.springframework.boot.autoconfigure.*; import org.springframework.stereotype.*; import org.springframework.web.bind.annotation.*; @RestController @EnableAutoConfiguration public class Example { @RequestMapping("/") String home() { return "Hello World!"; } public static void main(String[] args) throws Exception { SpringApplication.run(Example.class, args); } }
Although there isn’t much code here, quite a lot is going on. Let’s step though the important parts.
The first annotation on our Example
class is @RestController
. This is known as a
stereotype annotation. It provides hints for people reading the code, and for Spring,
that the class plays a specific role. In this case, our class is a web @Controller
so
Spring will consider it when handling incoming web requests.
The @RequestMapping
annotation provides “routing” information. It is telling Spring
that any HTTP request with the path "/
" should be mapped to the home
method. The
@RestController
annotation tells Spring to render the resulting string directly
back to the caller.
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The |
The second class-level annotation is @EnableAutoConfiguration
. This annotation tells
Spring Boot to “guess” how you will want to configure Spring, based on the jar
dependencies that you have added. Since spring-boot-starter-web
added Tomcat and
Spring MVC, the auto-configuration will assume that you are developing a web application
and setup Spring accordingly.
The final part of our application is the main
method. This is just a standard method
that follows the Java convention for an application entry point. Our main method delegates
to Spring Boot’s SpringApplication
class by calling run
. SpringApplication
will
bootstrap our application, starting Spring which will in turn start the auto-configured
Tomcat web server. We need to pass Example.class
as an argument to the run
method to
tell SpringApplication
which is the primary Spring component. The args
array is also
passed through to expose any command-line arguments.
At this point our application should work. Since we have used the
spring-boot-starter-parent
POM we have a useful run
goal that we can use to start
the application. Type mvn spring-boot:run
from the root project directory to start the
application:
$ mvn spring-boot:run . ____ _ __ _ _ /\\ / ___'_ __ _ _(_)_ __ __ _ \ \ \ \ ( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \ \\/ ___)| |_)| | | | | || (_| | ) ) ) ) ' |____| .__|_| |_|_| |_\__, | / / / / =========|_|==============|___/=/_/_/_/ :: Spring Boot :: (v1.1.0.RC1) ....... . . . ....... . . . (log output here) ....... . . . ........ Started Example in 2.222 seconds (JVM running for 6.514)
If you open a web browser to http://localhost:8080 you should see the following output:
Hello World!
To gracefully exit the application hit ctrl-c
.
Let’s finish our example by creating a completely self-contained executable jar file that we could run in production. Executable jars (sometimes called “fat jars”) are archives containing your compiled classes along with all of the jar dependencies that your code needs to run.
To create an executable jar we need to add the spring-boot-maven-plugin
to our
pom.xml
. Insert the following lines just below the dependencies
section:
<build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> </plugins> </build>
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The |
Save your pom.xml
and run mvn package
from the command line:
$ mvn package [INFO] Scanning for projects... [INFO] [INFO] ------------------------------------------------------------------------ [INFO] Building myproject 0.0.1-SNAPSHOT [INFO] ------------------------------------------------------------------------ [INFO] .... .. [INFO] --- maven-jar-plugin:2.4:jar (default-jar) @ myproject --- [INFO] Building jar: /Users/developer/example/spring-boot-example/target/myproject-0.0.1-SNAPSHOT.jar [INFO] [INFO] --- spring-boot-maven-plugin:1.1.0.RC1:repackage (default) @ myproject --- [INFO] ------------------------------------------------------------------------ [INFO] BUILD SUCCESS [INFO] ------------------------------------------------------------------------
If you look in the target
directory you should see myproject-0.0.1-SNAPSHOT.jar
. The
file should be around 10 Mb in size. If you want to peek inside, you can use jar tvf
:
$ jar tvf target/myproject-0.0.1-SNAPSHOT.jar
You should also see a much smaller file named myproject-0.0.1-SNAPSHOT.jar.original
in the target
directory. This is the original jar file that Maven created before it was
repackaged by Spring Boot.
To run that application, use the java -jar
command:
$ java -jar target/myproject-0.0.1-SNAPSHOT.jar . ____ _ __ _ _ /\\ / ___'_ __ _ _(_)_ __ __ _ \ \ \ \ ( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \ \\/ ___)| |_)| | | | | || (_| | ) ) ) ) ' |____| .__|_| |_|_| |_\__, | / / / / =========|_|==============|___/=/_/_/_/ :: Spring Boot :: (v1.1.0.RC1) ....... . . . ....... . . . (log output here) ....... . . . ........ Started Example in 3.236 seconds (JVM running for 3.764)
As before, to gracefully exit the application hit ctrl-c
.
Hopefully this section has provided you with some of the Spring Boot basics, and got you on your way to writing your own applications. If you’re a task-oriented type of developer you might want to jump over to http://spring.io and check out some of the getting started guides that solve specific “How do I do that with Spring” problems; we also have a Spring Boot specific How-to reference documentation.
Otherwise, the next logical step is to read Part III, “Using Spring Boot”. If you’re really impatient, you could also jump ahead and read about Spring Boot features.
This section goes into more detail about how you should use Spring Boot. It covers topics such as build systems, auto-configuration and run/deployment options. We also cover some Spring Boot best practices. Although there is nothing particularly special about Spring Boot (it is just another library that you can consume), there are a few recommendations that, when followed, will make your development process just a little easier.
If you’re just starting out with Spring Boot, you should probably read the Getting Started guide before diving into this section.
It is strongly recommended that you choose a build system that supports dependency management, and one that can consume artifacts published to the “Maven Central” repository. We would recommend that you choose Maven or Gradle. It is possible to get Spring Boot to work with other build systems (Ant for example), but they will not be particularly well supported.
Maven users can inherit from the spring-boot-starter-parent
project to obtain sensible
defaults. The parent project provides the following features:
<version>
tags for common
dependencies, inherited from the spring-boot-dependencies
POM.
To configure your project to inherit from the spring-boot-starter-parent
simply set
the parent
:
<!-- Inherit defaults from Spring Boot --> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>1.1.0.RC1</version> </parent>
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You should only need to specify the Spring Boot version number on this dependency. If you import additional starters, you can safely omit the version number. |
No everyone likes inheriting from the spring-boot-starter-parent
POM. You may have your
own corporate standard parent that you need to use, or you may just prefer to explicitly
declare all your Maven configuration.
If you don’t want to use the spring-boot-starter-parent
, you can still keep the benefit
of the dependency management (but not the plugin management) by using a scope=import
dependency:
<dependencyManagement> <dependencies> <dependency> <!-- Import dependency management from Spring Boot --> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-dependencies</artifactId> <version>1.1.0.RC1</version> <type>pom</type> <scope>import</scope> </dependency> </dependencies> </dependencyManagement>
The spring-boot-starter-parent
chooses fairly conservative Java compatibility. If you
want to follow our recommendation and use a later Java version you can add a
java.version
property:
<properties> <java.version>1.8</java.version> </properties>
Spring Boot includes a Maven plugin
that can package the project as an executable jar. Add the plugin to your <plugins>
section if you want to use it:
<build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> </plugins> </build>
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You only need to add the plugin, there is no need for to configure it unless you want to change the settings defined in the parent. |
Gradle users can directly import “starter POMs” in their dependencies
section. Unlike
Maven, there is no “super parent” to import to share some configuration.
apply plugin: 'java' repositories { mavenCentral() } dependencies { compile("org.springframework.boot:spring-boot-starter-web:1.1.0.RC1") }
The spring-boot-gradle-plugin
is also available and provides tasks to create executable jars and run projects from
source. It also adds a ResolutionStrategy
that enables you to
omit the version number
for “blessed” dependencies:
buildscript { repositories { mavenCentral() } dependencies { classpath("org.springframework.boot:spring-boot-gradle-plugin:1.1.0.RC1") } } apply plugin: 'java' apply plugin: 'spring-boot' repositories { mavenCentral() } dependencies { compile("org.springframework.boot:spring-boot-starter-web") testCompile("org.springframework.boot:spring-boot-starter-test") }
It is possible to build a Spring Boot project using Apache Ant, however, no special support or plugins are provided. Ant scripts can use the Ivy dependency system to import starter POMs.
See the Section 64.4, “Build an executable archive with Ant” “How-to” for more complete instructions.
Starter POMs are a set of convenient dependency descriptors that you can include in your
application. You get a one-stop-shop for all the Spring and related technology that you
need, without having to hunt through sample code and copy paste loads of dependency
descriptors. For example, if you want to get started using Spring and JPA for database
access, just include the spring-boot-starter-data-jpa
dependency in your project, and
you are good to go.
The starters contain a lot of the dependencies that you need to get a project up and running quickly and with a consistent, supported set of managed transitive dependencies.
The following application starters are provided by Spring Boot under the
org.springframework.boot
group:
Table 12.1. Spring Boot application starters
Name | Description |
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| The core Spring Boot starter, including auto-configuration support, logging and YAML. |
| Support for the “Advanced Message Queuing Protocol” via |
| Support for aspect-oriented programming including |
| Support for “Spring Batch” including HSQLDB database. |
| Support for the GemFire distributed data store including |
| Support for the “Java Persistence API” including |
| Support for the MongoDB NoSQL Database, including |
| Support for exposing Spring Data repositories over REST via |
| Support for the Apache Solr search platform, including |
| Support for the FreeMarker templating engine |
| Support for the Groovy templating engine |
| Support for “Java Message Service API” via HornetQ. |
| Support for common |
| JDBC Database support. |
| Support for |
| Support for the REDIS key-value data store, including |
| Support for |
| Support for |
| Support for |
| Support for |
| Support for common test dependencies, including JUnit, Hamcrest and Mockito along with
the |
| Support for the Thymeleaf templating engine, including integration with Spring. |
| Support for the Velocity templating engine |
| Support for full-stack web development, including Tomcat and |
| Support for websocket development with Tomcat. |
In addition to the application starters, the following starters can be used to add production ready features.
Table 12.2. Spring Boot production ready starters
Name | Description |
---|---|
| Adds production ready features such as metrics and monitoring. |
| Adds remote |
Finally, Spring Boot includes some starters that can be used if you want to exclude or swap specific technical facets.
Table 12.3. Spring Boot technical starters
Name | Description |
---|---|
| Imports the Jetty HTTP engine (to be used as an alternative to Tomcat) |
| Support the Log4J logging framework |
| Import Spring Boot’s default logging framework (Logback). |
| Import Spring Boot’s default HTTP engine (Tomcat). |
Tip | |
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For a list of additional community contributed starter POMs, see the
README file in the
|
Spring Boot does not require any specific code layout to work, however, there are some best practices that help.
When a class doesn’t include a package
declaration it is considered to be in the
“default package”. The use of the “default package” is generally discouraged, and
should be avoided. It can cause particular problems for Spring Boot applications that
use @ComponentScan
or @EntityScan
annotations, since every class from every jar,
will be read.
Tip | |
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We recommend that you follow Java’s recommended package naming conventions
and use a reversed domain name (for example, |
We generally recommend that you locate your main application class in a root package
above other classes. The @EnableAutoConfiguration
annotation is often placed on your
main class, and it implicitly defines a base “search package” for certain items. For
example, if you are writing a JPA application, the package of the
@EnableAutoConfiguration
annotated class will be used to search for @Entity
items.
Using a root package also allows the @ComponentScan
annotation to be used without
needing to specify a basePackage
attribute.
Here is a typical layout:
com +- example +- myproject +- Application.java | +- domain | +- Customer.java | +- CustomerRepository.java | +- service | +- CustomerService.java | +- web +- CustomerController.java
The Application.java
file would declare the main
method, along with the basic
@Configuration
.
package com.example.myproject; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.EnableAutoConfiguration; import org.springframework.context.annotation.ComponentScan; import org.springframework.context.annotation.Configuration; @Configuration @EnableAutoConfiguration @ComponentScan public class Application { public static void main(String[] args) { SpringApplication.run(Application.class, args); } }
Spring Boot favors Java-based configuration. Although it is possible to call
SpringApplication.run()
with an XML source, we generally recommend that your primary
source is a @Configuration
class. Usually the class that defines the main
method
is also a good candidate as the primary @Configuration
.
Tip | |
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Many Spring configuration examples have been published on the Internet that use XML
configuration. Always try to use the equivalent Java-base configuration if possible.
Searching for |
You don’t need to put all your @Configuration
into a single class. The @Import
annotation can be used to import additional configuration classes. Alternatively, you
can use @ComponentScan
to automatically pickup all Spring components, including
@Configuration
classes.
Spring Boot auto-configuration attempts to automatically configure your Spring
application based on the jar dependencies that you have added. For example, If
HSQLDB
is on your classpath, and you have not manually configured any database
connection beans, then we will auto-configure an in-memory database.
You need to opt-in to auto-configuration by adding the @EnableAutoConfiguration
annotation to one of your @Configuration
classes.
Tip | |
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You should only ever add one |
Auto-configuration is noninvasive, at any point you can start to define your own
configuration to replace specific parts of the auto-configuration. For example, if
you add your own DataSource
bean, the default embedded database support will back away.
If you need to find out what auto-configuration is currently being applied, and why,
starting your application with the --debug
switch. This will log an auto-configuration
report to the console.
If you find that specific auto-configure classes are being applied that you don’t want,
you can use the exclude attribute of @EnableAutoConfiguration
to disable them.
import org.springframework.boot.autoconfigure.*; import org.springframework.boot.autoconfigure.jdbc.*; import org.springframework.context.annotation.*; @Configuration @EnableAutoConfiguration(exclude={DataSourceAutoConfiguration.class}) public class MyConfiguration { }
You are free to use any of the standard Spring Framework techniques to define your beans
and their injected dependencies. For simplicity, we often find that using @ComponentScan
to find your beans, in combination with @Autowired
constructor injection works well.
If you structure your code as suggested above (locating your application class in a root
package), you can add @ComponentScan
without any arguments. All of your application
components (@Component
, @Service
, @Repository
, @Controller
etc.) will be
automatically registered as Spring Beans.
Here is an example @Service
Bean that uses constructor injection to obtain a
required RiskAssessor
bean.
package com.example.service; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Service; @Service public class DatabaseAccountService implements AccountService { private final RiskAssessor riskAssessor; @Autowired public DatabaseAccountService(RiskAssessor riskAssessor) { this.riskAssessor = riskAssessor; } // ... }
Tip | |
---|---|
Notice how using constructor injection allows the |
One of the biggest advantages of packaging your application as jar and using an embedded HTTP server is that you can run your application as you would any other. Debugging Spring Boot applications is also easy; you don’t need any special IDE plugins or extensions.
Note | |
---|---|
This section only covers jar based packaging, If you choose to package your application as a war file you should refer to your server and IDE documentation. |
You can run a Spring Boot application from your IDE as a simple Java application, however,
first you will need to import your project. Import steps will vary depending on your IDE
and build system. Most IDEs can import Maven projects directly, for example Eclipse users
can select Import...
→ Existing Maven Projects
from the File
menu.
If you can’t directly import your project into your IDE, you may be able to generate IDE meta-data using a build plugin. Maven includes plugins for Eclipse and IDEA; Gradle offers plugins for various IDEs.
Tip | |
---|---|
If you accidentally run a web application twice you will see a “Port already in
use” error. STS users can use the |
If you use the Spring Boot Maven or Gradle plugins to create an executable jar you can
run your application using java -jar
. For example:
$ java -jar target/myproject-0.0.1-SNAPSHOT.jar
It is also possible to run a packaged application with remote debugging support enabled. This allows you to attach a debugger to your packaged application:
$ java -Xdebug -Xrunjdwp:server=y,transport=dt_socket,address=8000,suspend=n \ -jar target/myproject-0.0.1-SNAPSHOT.jar
The Spring Boot Maven plugin includes a run
goal which can be used to quickly compile
and run your application. Applications run in an exploded form, and you can edit
resources for instant “hot” reload.
$ mvn spring-boot:run
Useful operating system environment variable:
$ export MAVEN_OPTS=-Xmx1024m -XX:MaxPermSize=128M -Djava.security.egd=file:/dev/./urandom
(The "egd" setting is to speed up Tomcat startup by giving it a faster source of entropy for session keys.)
The Spring Boot Gradle plugin also includes a run
goal which can be used to run
your application in an exploded form. The bootRun
task is added whenever you import
the spring-boot-plugin
$ gradle bootRun
Useful operating system environment variable:
$ export JAVA_OPTS=-Xmx1024m -XX:MaxPermSize=128M -Djava.security.egd=file:/dev/./urandom
Since Spring Boot applications are just plain Java applications, JVM hot-swapping should work out of the box. JVM hot swapping is somewhat limited with the bytecode that it can replace, for a more complete solution the Spring Loaded project, or JRebel can be used.
See the Hot swapping “How-to” section for details.
Executable jars can be used for production deployment. As they are self contained, they are also ideally suited for cloud-based deployment.
For additional “production ready” features, such as health, auditing and metric REST
or JMX end-points; consider adding spring-boot-actuator
. See
Part V, “Production-ready features” for details.
You should now have good understanding of how you can use Spring Boot along with some best practices that you should follow. You can now go on to learn about specific Spring Boot features in depth, or you could skip ahead and read about the “production ready” aspects of Spring Boot.
This section dives into the details of Spring Boot. Here you can learn about the key features that you will want to use and customize. If you haven’t already, you might want to read the Part II, “Getting started” and Part III, “Using Spring Boot” sections so that you have a good grounding of the basics.
The SpringApplication
class provides a convenient way to bootstrap a Spring application
that will be started from a main()
method. In many situations you can just delegate to
the static SpringApplication.run
method:
public static void main(String[] args) { SpringApplication.run(MySpringConfiguration.class, args); }
When your application starts you should see something similar to the following:
. ____ _ __ _ _ /\\ / ___'_ __ _ _(_)_ __ __ _ \ \ \ \ ( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \ \\/ ___)| |_)| | | | | || (_| | ) ) ) ) ' |____| .__|_| |_|_| |_\__, | / / / / =========|_|==============|___/=/_/_/_/ :: Spring Boot :: v1.1.0.RC1 2013-07-31 00:08:16.117 INFO 56603 --- [ main] o.s.b.s.app.SampleApplication : Starting SampleApplication v0.1.0 on mycomputer with PID 56603 (/apps/myapp.jar started by pwebb) 2013-07-31 00:08:16.166 INFO 56603 --- [ main] ationConfigEmbeddedWebApplicationContext : Refreshing org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext@6e5a8246: startup date [Wed Jul 31 00:08:16 PDT 2013]; root of context hierarchy 2014-03-04 13:09:54.912 INFO 41370 --- [ main] .t.TomcatEmbeddedServletContainerFactory : Server initialized with port: 8080 2014-03-04 13:09:56.501 INFO 41370 --- [ main] o.s.b.s.app.SampleApplication : Started SampleApplication in 2.992 seconds (JVM running for 3.658)
By default INFO
logging messages will be shown, including some relevant startup details
such as the user that launched the application.
The banner that is printed on start up can be changed by adding a banner.txt
file
to your classpath, or by setting banner.location
to the location of such a file.
If the file has an unusual encoding you can set banner.encoding
(default is UTF-8).
If the SpringApplication
defaults aren’t to your taste you can instead create a local
instance and customize it. For example, to turn off the banner you would write:
public static void main(String[] args) { SpringApplication app = new SpringApplication(MySpringConfiguration.class); app.setShowBanner(false); app.run(args); }
Note | |
---|---|
The constructor arguments passed to |
It is also possible to configure the SpringApplication
using an application.properties
file. See Chapter 21, Externalized Configuration for details.
For a complete list of the configuration options, see the
SpringApplication
Javadoc.
If you need to build an ApplicationContext
hierarchy (multiple contexts with a
parent/child relationship), or if you just prefer using a “fluent” builder API, you
can use the SpringApplicationBuilder
.
The SpringApplicationBuilder
allows you to chain together multiple method calls, and
includes parent
and child
methods that allow you to create a hierarchy.
For example:
new SpringApplicationBuilder() .showBanner(false) .sources(Parent.class) .child(Application.class) .run(args);
Note | |
---|---|
There are some restrictions when creating an |
In addition to the usual Spring Framework events, such as
ContextRefreshedEvent
,
a SpringApplication
sends some additional application events. Some events are actually
triggered before the ApplicationContext
is created.
You can register event listeners in a number of ways, the most common being
SpringApplication.addListeners(...)
method.
Application events are sent in the following order, as your application runs:
ApplicationStartedEvent
is sent at the start of a run, but before any
processing except the registration of listeners and initializers.
ApplicationEnvironmentPreparedEvent
is sent when the Environment
to be used in
the context is known, but before the context is created.
ApplicationPreparedEvent
is sent just before the refresh is started, but after bean
definitions have been loaded.
ApplicationFailedEvent
is sent if there is an exception on startup.
Tip | |
---|---|
You often won’t need to use application events, but it can be handy to know that they exist. Internally, Spring Boot uses events to handle a variety of tasks. |
A SpringApplication
will attempt to create the right type of ApplicationContext
on
your behalf. By default, an AnnotationConfigApplicationContext
or
AnnotationConfigEmbeddedWebApplicationContext
will be used, depending on whether you
are developing a web application or not.
The algorithm used to determine a “web environment” is fairly simplistic (based on the
presence of a few classes). You can use setWebEnvironment(boolean webEnvironment)
if
you need to override the default.
It is also possible to take complete control of the ApplicationContext
type that will
be used by calling setApplicationContextClass(...)
.
Tip | |
---|---|
It is often desirable to call |
If you want access to the raw command line arguments, or you need to run some specific code
once the SpringApplication
has started you can implement the CommandLineRunner
interface. The run(String... args)
method will be called on all Spring beans
implementing this interface.
import org.springframework.boot.* import org.springframework.stereotype.* @Component public class MyBean implements CommandLineRunner { public void run(String... args) { // Do something... } }
You can additionally implement the org.springframework.core.Ordered
interface or use the
org.springframework.core.annotation.Order
annotation if several CommandLineRunner
beans are defined that must be called in a specific order.
Each SpringApplication
will register a shutdown hook with the JVM to ensure that the
ApplicationContext
is closed gracefully on exit. All the standard Spring lifecycle
callbacks (such as the DisposableBean
interface, or the @PreDestroy
annotation) can
be used.
In addition, beans may implement the org.springframework.boot.ExitCodeGenerator
interface if they wish to return a specific exit code when the application ends.
Spring Boot allows you to externalize your configuration so you can work with the same
application code in different environments. You can use properties files, YAML files,
environment variables and command-line arguments to externalize configuration. Property
values can be injected directly into your beans using the @Value
annotation, accessed
via Spring’s Environment
abstraction or bound to structured objects.
Spring Boot uses a very particular PropertySource
order that is designed to allow
sensible overriding of values, properties are considered in the the following order:
System.getProperties()
).
RandomValuePropertySource
that only has properties in random.*
.
@PropertySource
annotations on your @Configuration
classes.
application.properties
including YAML and profile variants).
application.properties
including YAML and profile variants).
SpringApplication.setDefaultProperties
).
To provide a concrete example, suppose you develop a @Component
that uses a
name
property:
import org.springframework.stereotype.* import org.springframework.beans.factory.annotation.* @Component public class MyBean { @Value("${name}") private String name; // ... }
You can bundle an application.properties
inside your jar that provides a sensible
default name
. When running in production, an application.properties
can be provided
outside of your jar that overrides name
; and for one-off testing, you can launch with
a specific command line switch (e.g. java -jar app.jar --name="Spring"
).
The RandomValuePropertySource
is useful for injecting random values (e.g. into secrets
or test cases). It can produce integers, longs or strings, e.g.
my.secret=${random.value} my.number=${random.int} my.bignumber=${random.long} my.number.less.than.ten=${random.int(10)} my.number.in.range=${random.int[1024,65536]}
The random.int*
syntax is OPEN value (,max) CLOSE
where the OPEN,CLOSE
are any
character and value,max
are integers. If max
is provided then value
is the minimum
value and max
is the maximum (exclusive).
By default SpringApplication
will convert any command line option arguments (starting
with “--”, e.g. --server.port=9000
) to a property
and add it to the Spring
Environment
. As mentioned above, command line properties always take precedence over
other property sources.
If you don’t want command line properties to be added to the Environment
you can disable
them using SpringApplication.setAddCommandLineProperties(false)
.
SpringApplication
will load properties from application.properties
files in the
following locations and add them to the Spring Environment
:
/config
subdir of the current directory.
/config
package
The list is ordered by precedence (locations higher in the list override lower items).
Note | |
---|---|
You can also use YAML (.yml) files as an alternative to .properties. |
If you don’t like application.properties
as the configuration file name you can switch
to another by specifying a spring.config.name
environment property. You can also refer
to an explicit location using the spring.config.location
environment property
(comma-separated list of directory locations, or file paths).
$ java -jar myproject.jar --spring.config.name=myproject
or
$ java -jar myproject.jar --spring.config.location=classpath:/default.properties,classpath:/override.properties
If spring.config.location
contains directories (as opposed to files) they should end
in /
(and will be appended with the names generated from spring.config.name
before
being loaded). The default search path classpath:,classpath:/config,file:,file:config/
is always used, irrespective of the value of spring.config.location
. In that way you
can set up default values for your application in application.properties
(or whatever
other basename you choose with spring.config.name
) and override it at runtime with a
different file, keeping the defaults.
In addition to application.properties
files, profile specific properties can also be
defined using the naming convention application-{profile}.properties
.
Profile specific properties are loaded from the same locations as standard
application.properties
, with profiles specific files overriding the default ones.
The values in application.properties
are filtered through the existing Environment
when they are used so you can refer back to previously defined values (e.g. from System
properties).
app.name=MyApp app.description=${app.name} is a Spring Boot application
Tip | |
---|---|
You can also use this technique to create “short” variants of existing Spring Boot properties. See the Section 54.3, “Use “short” command line arguments” how-to for details. |
YAML is a superset of JSON, and as such is a very convenient format
for specifying hierarchical configuration data. The SpringApplication
class will
automatically support YAML as an alternative to properties whenever you have the
SnakeYAML library on your classpath.
Note | |
---|---|
If you use “starter POMs” SnakeYAML will be automatically provided via
|
Spring Boot provides two convenient classes that can be used to load YAML documents. The
YamlPropertiesFactoryBean
will load YAML as Properties
and the YamlMapFactoryBean
will load YAML as a Map
.
For example, the following YAML document:
dev: url: http://dev.bar.com name: Developer Setup prod: url: http://foo.bar.com name: My Cool App
Would be transformed into these properties:
environments.dev.url=http://dev.bar.com environments.dev.name=Developer Setup environments.prod.url=http://foo.bar.com environments.prod.name=My Cool App
YAML lists are represented as property keys with [index]
dereferencers,
for example this YAML:
my: servers: - dev.bar.com - foo.bar.com
Would be transformed into these properties:
my.servers[0]=dev.bar.com my.servers[1]=foo.bar.com
To bind to properties like that using the Spring DataBinder
utilities (which is what
@ConfigurationProperties
does) you need to have a property in the target bean of type
java.util.List
(or Set
) and you either need to provide a setter, or initialize it
with a mutable value, e.g. this will bind to the properties above
@ConfigurationProperties(prefix="my") public class Config { private List<String> servers = new ArrayList<String>(); public List<String> getServers() { return this.servers; } }
The YamlPropertySourceLoader
class can be used to expose YAML as a PropertySource
in the Spring Environment
. This allows you to use the familiar @Value
annotation with
placeholders syntax to access YAML properties.
You can specify multiple profile-specific YAML document in a single file by
by using a spring.profiles
key to indicate when the document applies. For example:
server: address: 192.168.1.100 --- spring: profiles: development server: address: 127.0.0.1 --- spring: profiles: production server: address: 192.168.1.120
Using the @Value("${property}")
annotation to inject configuration properties can
sometimes be cumbersome, especially if you are working with multiple properties or
your data is hierarchical in nature. Spring Boot provides an alternative method
of working with properties that allows strongly typed beans to govern and validate
the configuration of your application. For example:
@Component @ConfigurationProperties(prefix="connection") public class ConnectionSettings { private String username; private InetAddress remoteAddress; // ... getters and setters }
When the @EnableConfigurationProperties
annotation is applied to your @Configuration
,
any beans annotated with @ConfigurationProperties
will be automatically configured
from the Environment
properties. This style of configuration works particularly well
with the SpringApplication
external YAML configuration:
# application.yml connection: username: admin remoteAddress: 192.168.1.1 # additional configuration as required
To work with @ConfigurationProperties
beans you can just inject them in the same way
as any other bean.
@Service public class MyService { @Autowired private ConnectionSettings connection; //... @PostConstruct public void openConnection() { Server server = new Server(); this.connection.configure(server); } }
It is also possible to shortcut the registration of @ConfigurationProperties
bean
definitions by simply listing the properties classes directly in the
@EnableConfigurationProperties
annotation:
@Configuration @EnableConfigurationProperties(ConnectionSettings.class) public class MyConfiguration { }
Spring Boot uses some relaxed rules for binding Environment
properties to
@ConfigurationProperties
beans, so there doesn’t need to be an exact match between
the Environment
property name and the bean property name. Common examples where this
is useful include underscore separated (e.g. context_path
binds to contextPath
), and
capitalized (e.g. PORT
binds to port
) environment properties.
Spring will attempt to coerce the external application properties to the right type when
it binds to the @ConfigurationProperties
beans. If you need custom type conversion you
can provide a ConversionService
bean (with bean id conversionService
) or custom
property editors (via a CustomEditorConfigurer
bean).
Spring Boot will attempt to validate external configuration, by default using JSR-303
(if it is on the classpath). You can simply add JSR-303 javax.validation
constraint
annotations to your @ConfigurationProperties
class:
@Component @ConfigurationProperties(prefix="connection") public class ConnectionSettings { @NotNull private InetAddress remoteAddress; // ... getters and setters }
You can also add a custom Spring Validator
by creating a bean definition called
configurationPropertiesValidator
.
Tip | |
---|---|
The |
Spring Profiles provide a way to segregate parts of your application configuration and
make it only available in certain environments. Any @Component
or @Configuration
can
be marked with @Profile
to limit when it is loaded:
@Configuration @Profile("production") public class ProductionConfiguraiton { // ... }
In the normal Spring way, you can use a spring.profiles.active
Environment
property to specify which profiles are active. You can
specify the property in any of the usual ways, for example you could
include it in your application.properties
:
spring.profiles.active=dev,hsqldb
or specify on the command line using the switch --spring.profiles.active=dev,hsqldb
.
The spring.profiles.active
property follows the same ordering rules as other
properties, the highest PropertySource
will win. This means that you can specify
active profiles in application.properties
then replace them using the command line
switch.
Sometimes it is useful to have profile specific properties that add to the active
profiles rather than replace them. The spring.profiles.include
property can be used
to unconditionally add active profiles. The SpringApplication
entry point also has
a Java API for setting additional profiles (i.e. on top of those activated by the
spring.profiles.active
property): see the setAdditionalProfiles()
method.
For example, when an application with following properties is run using the switch
--spring.profiles.active=prod
the proddb
and prodmq
profiles will also be activated:
--- my.property: fromyamlfile --- spring.profiles: prod spring.profiles.include: proddb,prodmq
You can programmatically set active profiles by calling
SpringApplication.setAdditionalProfiles(...)
before your application runs. It is also
possible to activate profiles using Spring’s ConfigurableEnvironment
interface.
Profile specific variants of both application.properties
(or application.yml
) and
files referenced via @ConfigurationProperties
are considered as files are loaded.
See Section 21.3, “Profile specific properties” for details.
Spring Boot uses Commons Logging for all internal logging, but leaves the underlying log implementation open. Default configurations are provided for Java Util Logging, Log4J and Logback. In each case there is console output and file output (rotating, 10 Mb file size).
By default, If you use the “Starter POMs”, Logback will be used for logging. Appropriate Logback routing is also included to ensure that dependent libraries that use Java Util Logging, Commons Logging, Log4J or SLF4J will all work correctly.
Tip | |
---|---|
There are a lot of logging frameworks available for Java. Don’t worry if the above list seems confusing, generally you won’t need to change your logging dependencies and the Spring Boot defaults will work just fine. |
The default log output from Spring Boot looks like this:
2014-03-05 10:57:51.112 INFO 45469 --- [ main] org.apache.catalina.core.StandardEngine : Starting Servlet Engine: Apache Tomcat/7.0.52 2014-03-05 10:57:51.253 INFO 45469 --- [ost-startStop-1] o.a.c.c.C.[Tomcat].[localhost].[/] : Initializing Spring embedded WebApplicationContext 2014-03-05 10:57:51.253 INFO 45469 --- [ost-startStop-1] o.s.web.context.ContextLoader : Root WebApplicationContext: initialization completed in 1358 ms 2014-03-05 10:57:51.698 INFO 45469 --- [ost-startStop-1] o.s.b.c.e.ServletRegistrationBean : Mapping servlet: 'dispatcherServlet' to [/] 2014-03-05 10:57:51.702 INFO 45469 --- [ost-startStop-1] o.s.b.c.embedded.FilterRegistrationBean : Mapping filter: 'hiddenHttpMethodFilter' to: [/*]
The following items are output:
ERROR
, WARN
, INFO
, DEBUG
or TRACE
.
---
separator to distinguish the start of actual log messages.
The default log configuration will echo messages to the console as they are written. By
default ERROR
, WARN
and INFO
level messages are logged. To also log DEBUG
level
messages to the console you can start your application with a --debug
flag.
$ java -jar myapp.jar --debug
If your terminal supports ANSI, color output will be used to aid readability.
By default, log files are written to spring.log
in your temp
directory and rotate at
10 Mb. You can easily customize the output folder by setting the logging.path
property
(for example in your application.properties
). It is also possible to change the filename
using a logging.file
property.
As with console output, ERROR
, WARN
and INFO
level messages are logged by default.
The various logging systems can be activated by including the appropriate libraries on
the classpath, and further customized by providing a suitable configuration file in the
root of the classpath, or in a location specified by the Spring Environment
property
logging.config
. (Note however that since logging is initialized before the ApplicationContext
is created, it isn't possible to control logging from `@PropertySources
in Spring
@Configuration
files. System properties and the conventional Spring Boot external
configuration files work just fine.)
Depending on your logging system, the following files will be loaded:
Logging System | Customization |
---|---|
Logback |
|
Log4j |
|
JDK (Java Util Logging) |
|
To help with the customization some other properties are transferred from the Spring
Environment
to System properties:
Spring Environment | System Property | Comments |
---|---|---|
|
| Used in default log configuration if defined. |
|
| Used in default log configuration if defined. |
|
| The current process ID (discovered if possible and when not already defined as an OS environment variable). |
All the logging systems supported can consult System properties when parsing their
configuration files. See the default configurations in spring-boot.jar
for examples.
Warning | |
---|---|
There are know classloading issues with Java Util Logging that cause problems when running from an “executable jar”. We recommend that you avoid it if at all possible. |
Spring Boot is well suited for web application development. You can easily create a
self-contained HTTP server using embedded Tomcat or Jetty. Most web applications will
use the spring-boot-starter-web
module to get up and running quickly.
If you haven’t yet developed a Spring Boot web application you can follow the "Hello World!" example in the Getting started section.
The Spring Web MVC framework (often referred to as simply “Spring MVC”) is a rich
“model view controller” web framework. Spring MVC lets you create special @Controller
or @RestController
beans to handle incoming HTTP requests. Methods in your controller
are mapped to HTTP using @RequestMapping
annotations.
Here is a typical example @RestController
to serve JSON data:
@RestController @RequestMapping(value="/users") public class MyRestController { @RequestMapping(value="/{user}", method=RequestMethod.GET) public User getUser(@PathVariable Long user) { // ... } @RequestMapping(value="/{user}/customers", method=RequestMethod.GET) List<Customer> getUserCustomers(@PathVariable Long user) { // ... } @RequestMapping(value="/{user}", method=RequestMethod.DELETE) public User deleteUser(@PathVariable Long user) { // ... } }
Spring MVC is part of the core Spring Framework and detailed information is available in the reference documentation. There are also several guides available at http://spring.io/guides that cover Spring MVC.
Spring Boot provides auto-configuration for Spring MVC that works well with most applications.
The auto-configuration adds the following features on top of Spring’s defaults:
ContentNegotiatingViewResolver
and BeanNameViewResolver
beans.
Converter
, GenericConverter
, Formatter
beans.
HttpMessageConverters
(see below).
MessageCodeResolver
(see below)
index.html
support.
Favicon
support.
If you want to take complete control of Spring MVC, you can add your own @Configuration
annotated with @EnableWebMvc
. If you want to keep Spring Boot MVC features, and
you just want to add additional MVC configuration (interceptors,
formatters, view controllers etc.) you can add your own @Bean
of type
WebMvcConfigurerAdapter
, but without @EnableWebMvc
.
Spring MVC uses the HttpMessageConverter
interface to convert HTTP requests and
responses. Sensible defaults are included out of the box, for example Objects can be
automatically converted to JSON (using the Jackson library) or XML (using JAXB).
If you need to add or customize converters you can use Spring Boot’s
HttpMessageConverters
class:
import org.springframework.boot.autoconfigure.web.HttpMessageConverters; import org.springframework.context.annotation.*; import org.springframework.http.converter.*; @Configuration public class MyConfiguration { @Bean public HttpMessageConverters customConverters() { HttpMessageConverter<?> additional = ... HttpMessageConverter<?> another = ... return new HttpMessageConverters(additional, another); } }
Spring MVC has a strategy for generating error codes for rendering error messages
from binding errors: MessageCodesResolver
. Spring Boot will create one for you if
you set the spring.mvc.message-codes-resolver.format
property PREFIX_ERROR_CODE
or
POSTFIX_ERROR_CODE
(see the enumeration in DefaultMessageCodesResolver.Format
).
By default Spring Boot will serve static content from a folder called /static
(or
/public
or /resources
or /META-INF/resources
) in the classpath or from the root
of the ServletContext
. It uses the ResourceHttpRequestHandler
from Spring MVC so you
can modify that behavior by adding your own WebMvcConfigurerAdapter
and overriding the
addResourceHandlers
method.
In a stand-alone web application the default servlet from the container is also
enabled, and acts as a fallback, serving content from the root of the ServletContext
if
Spring decides not to handle it. Most of the time this will not happen (unless you modify
the default MVC configuration) because Spring will always be able to handle requests
through the DispatcherServlet
.
In addition to the “standard” static resource locations above, a special case is made for
Webjars content. Any resources with a path in /webjars/**
will
be served from jar files if they are packaged in the Webjars format.
Tip | |
---|---|
Do not use the |
As well as REST web services, you can also use Spring MVC to serve dynamic HTML content. Spring MVC supports a variety of templating technologies including Velocity, FreeMarker and JSPs. Many other templating engines also ship their own Spring MVC integrations.
Spring Boot includes auto-configuration support for the following templating engines:
When you’re using one of these templating engines with the default configuration, your templates
will be picked up automatically from src/main/resources/templates
.
Tip | |
---|---|
JSPs should be avoided if possible, there are several known limitations when using them with embedded servlet containers. |
Spring Boot provides an /error
mapping by default that handles all errors in a
sensible way, and it is registered as a “global” error page in the servlet container.
For machine clients it will produce a JSON response with details of the error, the HTTP
status and the exception message. For browser clients there is a “whitelabel” error
view that renders the same data in HTML format (to customize it just add a View
that
resolves to “error”). To replace the default behaviour completely you can implement
ErrorController
and register a bean definition of that type, or simply add a bean
of type ErrorAttributes
to use the existing mechanism but replace the contents.
If you want more specific error pages for some conditions, the embedded servlet containers support a uniform Java DSL for customizing the error handling. For example:
@Bean public EmbeddedServletContainerCustomizer containerCustomizer(){ return new MyCustomizer(); } // ... private static class MyCustomizer implements EmbeddedServletContainerCustomizer { @Override public void customize(ConfigurableEmbeddedServletContainer factory) { factory.addErrorPages(new ErrorPage(HttpStatus.BAD_REQUEST, "/400")); } }
You can also use regular Spring MVC features like @ExceptionHandler
methods and @ControllerAdvice
.
The ErrorController
will then pick up any unhandled exceptions.
Spring Boot includes support for embedded Tomcat and Jetty servers. Most developers will
simply use the appropriate “Starter POM” to obtain a fully configured instance. By
default both Tomcat and Jetty will listen for HTTP requests on port 8080
.
When using an embedded servlet container you can register Servlets and Filters directly as
Spring beans. This can be particularly convenient if you want to refer to a value from
your application.properties
during configuration.
By default, if the context contains only a single Servlet it will be mapped to /
. In
the case of multiple Servlets beans the bean name will be used as a path prefix. Filters
will map to /*
.
If convention-based mapping is not flexible enough you can use the
ServletRegistrationBean
and FilterRegistrationBean
classes for complete control. You
can also register items directly if your bean implements the ServletContextInitializer
interface.
Under the hood Spring Boot uses a new type of ApplicationContext
for embedded
servlet container support. The EmbeddedWebApplicationContext
is a special
type of WebApplicationContext
that bootstraps itself by searching for a single
EmbeddedServletContainerFactory
bean. Usually a TomcatEmbeddedServletContainerFactory
or JettyEmbeddedServletContainerFactory
will have been auto-configured.
Note | |
---|---|
You usually won’t need to be aware of these implementation classes. Most
applications will be auto-configured and the appropriate |
Common servlet container settings can be configured using Spring Environment
properties. Usually you would define the properties in your application.properties
file.
Common server settings include:
server.port
— The listen port for incoming HTTP requests.
server.address
— The interface address to bind to.
server.sessionTimeout
— A session timeout.
See the ServerProperties
class for a complete list.
If you need to configure your embdedded servlet container programmatically you can register
a Spring bean that implements the EmbeddedServletContainerCustomizer
interface.
EmbeddedServletContainerCustomizer
provides access to the
ConfigurableEmbeddedServletContainerFactory
which includes numerous customization
setter methods.
import org.springframework.boot.context.embedded.*; import org.springframework.stereotype.Component; @Component public class CustomizationBean implements EmbeddedServletContainerCustomizer { @Override public void customize(ConfigurableEmbeddedServletContainer container) { container.setPort(9000); } }
If the above customization techniques are too limited, you can register the
TomcatEmbeddedServletContainerFactory
or JettyEmbeddedServletContainerFactory
bean
yourself.
@Bean public EmbeddedServletContainerFactory servletContainer() { TomcatEmbeddedServletContainerFactory factory = new TomcatEmbeddedServletContainerFactory(); factory.setPort(9000); factory.setSessionTimeout(10, TimeUnit.MINUTES); factory.addErrorPages(new ErrorPage(HttpStatus.404, "/notfound.html"); return factory; }
Setters are provided for many configuration options. Several protected method “hooks” are also provided should you need to do something more exotic. See the source code documentation for details.
When running a Spring Boot application that uses an embedded servlet container (and is packaged as an executable archive), there are some limitations in the JSP support.
There is a JSP sample so you can see how to set things up.
If Spring Security is on the classpath then web applications will be secure by default
with “basic” authentication on all HTTP endpoints. To add method-level security to a web
application you can also add @EnableGlobalMethodSecurity
with your desired settings.
Additional information can be found in the Spring
Security Reference.
The default AuthenticationManager
has a single user (“user” username and random
password, printed at INFO level when the application starts up)
Using default security password: 78fa095d-3f4c-48b1-ad50-e24c31d5cf35
You can change the password by providing a security.user.password
. This and other
useful properties are externalized via
SecurityProperties
(properties prefix "security").
The default security configuration is implemented in SecurityAutoConfiguration
and in
the classes imported from there (SpringBootWebSecurityConfiguration
for web security
and AuthenticationManagerConfiguration
for authentication configuration which is also
relevant in non-web applications). To switch off the Boot default configuration
completely in a web application you can add a bean with @EnableWebSecurity
. To customize
it you normally use external properties and beans of type WebConfigurerAdapter
(e.g. to
add form-based login). There are several secure applications in the
Spring Boot samples to get you started with common
use cases.
The basic features you get out of the box in a web application are:
AuthenticationManager
bean with in-memory store and a single user (see
SecurityProperties.User
for the properties of the user).
/css/**
, /js/**
,
/images/**
and **/favicon.ico
).
ApplicationEventPublisher
(successful and
unsuccessful authentication and access denied).
All of the above can be switched on and off or modified using external properties
(security.*
). To override the access rules without changing any other autoconfigured
features add a @Bean
of type WebConfigurerAdapter
with
@Order(SecurityProperties.ACCESS_OVERRIDE_ORDER)
.
If the Actuator is also in use, you will find:
AuditEvents
and published to the AuditService
.
The Actuator security features can be modified using external properties
(management.security.*
). To override the application access rules
add a @Bean
of type WebConfigurerAdapter
and use
@Order(SecurityProperties.ACCESS_OVERRIDE_ORDER)
if you don’t want to override
the actuator access rules, or @Order(ManagementServerProperties.ACCESS_OVERRIDE_ORDER)
if you do want to override the actuator access rules.
The Spring Framework provides extensive support for working with SQL databases. From
direct JDBC access using JdbcTemplate
to complete “object relational mapping”
technologies such as Hibernate. Spring Data provides an additional level of functionality,
creating Repository
implementations directly from interfaces and using conventions to
generate queries from your method names.
Java’s javax.sql.DataSource
interface provides a standard method of working with
database connections. Traditionally a DataSource uses a URL
along with some
credentials to establish a database connection.
It’s often convenient to develop applications using an in-memory embedded database. Obviously, in-memory databases do not provide persistent storage; you will need to populate your database when your application starts and be prepared to throw away data when your application ends.
Tip | |
---|---|
The “How-to” section includes a section on how to initialize a database |
Spring Boot can auto-configure embedded H2, HSQL and Derby databases. You don’t need to provide any connection URLs, simply include a build dependency to the embedded database that you want to use.
For example, typical POM dependencies would be:
<dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-data-jpa</artifactId> </dependency> <dependency> <groupId>org.hsqldb</groupId> <artifactId>hsqldb</artifactId> <scope>runtime</scope> </dependency>
Note | |
---|---|
You need a dependency on |
Production database connections can also be auto-configured using a pooling
DataSource
. Here’s the algorithm for choosing a specific implementation.
DataSource
for its performance and concurrency, so if
that is available we always choose it.
If you use the spring-boot-starter-jdbc
or spring-boot-starter-data-jpa
“starter POMs” you will automcatically get a dependency to tomcat-jdbc
.
Note | |
---|---|
Additional connection pools can always be configured manually. If you define your
own |
DataSource configuration is controlled by external configuration properties in
spring.datasource.*
. For example, you might declare the following section
in application.properties
:
spring.datasource.url=jdbc:mysql://localhost/test spring.datasource.username=dbuser spring.datasource.password=dbpass spring.datasource.driverClassName=com.mysql.jdbc.Driver
See AbstractDataSourceConfiguration
for more of the supported options.
Note | |
---|---|
For a pooling |
Spring’s JdbcTemplate
and NamedParameterJdbcTemplate
classes are auto-configured and
you can @Autowire
them directly into your own beans:
import org.springframework.beans.factory.annotation.Autowired; import org.springframework.jdbc.core.JdbcTemplate; import org.springframework.stereotype.Component; @Component public class MyBean { private final JdbcTemplate jdbcTemplate; @Autowired public MyBean(JdbcTemplate jdbcTemplate) { this.jdbcTemplate = jdbcTemplate; } // ... }
The Java Persistence API is a standard technology that allows you to “map” objects to
relational databases. The spring-boot-starter-data-jpa
POM provides a quick way to get
started. It provides the following key dependencies:
Tip | |
---|---|
We won’t go into too many details of JPA or Spring Data here. You can follow the “Accessing Data with JPA” guide from http://spring.io and read the Spring Data JPA and Hibernate reference documentation. |
Traditionally, JPA “Entity” classes are specified in a persistence.xml
file. With
Spring Boot this file is not necessary and instead “Entity Scanning” is used. By
default all packages below your main configuration class (the one annotated with
@EnableAutoConfiguration
) will be searched.
Any classes annotated with @Entity
, @Embeddable
or @MappedSuperclass
will be
considered. A typical entity class would look something like this:
package com.example.myapp.domain; import java.io.Serializable; import javax.persistence.*; @Entity public class City implements Serializable { @Id @GeneratedValue private Long id; @Column(nullable = false) private String name; @Column(nullable = false) private String state; // ... additional members, often include @OneToMany mappings protected City() { // no-args constructor required by JPA spec // this one is protected since it shouldn't be used directly } public City(String name, String state) { this.name = name; this.country = country; } public String getName() { return this.name; } public String getState() { return this.state; } // ... etc }
Tip | |
---|---|
You can customize entity scanning locations using the |
Spring Data JPA repositories are interfaces that you can define to access data. JPA
queries are created automatically from your method names. For example, a CityRepository
interface might declare a findAllByState(String state)
method to find all cities
in a given state.
For more complex queries you can annotate your method using Spring Data’s
Query
annotation.
Spring Data repositories usually extend from the
Repository
or
CrudRepository
interfaces. If you are using
auto-configuration, repositories will be searched from the package containing your
main configuration class (the one annotated with @EnableAutoConfiguration
) down.
Here is a typical Spring Data repository:
package com.example.myapp.domain; import org.springframework.data.domain.*; import org.springframework.data.repository.*; public interface CityRepository extends Repository<City, Long> { Page<City> findAll(Pageable pageable); City findByNameAndCountryAllIgnoringCase(String name, String country); }
Tip | |
---|---|
We have barely scratched the surface of Spring Data JPA. For complete details check their reference documentation. |
By default JPA database will be automatically created only if you use an embedded
database (H2, HSQL or Derby). You can explicitly configure JPA settings using
spring.jpa.*
properties. For example, to create and drop tables you can add the
following to your application.properties
.
spring.jpa.hibernate.ddl-auto=create-drop
Note | |
---|---|
Hibernate’s own internal property name for this (if you happen to remember it
better) is |
Spring Data provides additional projects that help you access a variety of NoSQL technologies including MongoDB, Neo4J, Redis, Gemfire, Couchbase and Cassandra. Spring Boot provides auto-configuration for MongoDB; you can make use of the other projects, but you will need to configure them yourself. Refer to the appropriate reference documentation at http://projects.spring.io/spring-data.
MongoDB is an open-source NoSQL document database that uses a
JSON-like schema instead of traditional table-based relational data. Spring Boot offers
several conveniences for working with MongoDB, including the The
spring-boot-starter-data-mongodb
“Starter POM”.
You can inject an auto-configured com.mongodb.Mongo
instance as you would any other
Spring Bean. By default the instance will attempt to connect to a MongoDB server using
the URL mongodb://localhost/test
:
import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Component; import com.mongodb.Mongo; @Component public class MyBean { private final Mongo mongo; @Autowired public MyBean(Mongo mongo) { this.mongo = mongo; } // ... }
You can set spring.data.mongodb.uri
property to change the url
, or alternatively
specify a host
/port
. For example, you might declare the following in your
application.properties
:
spring.data.mongodb.host=mongoserver spring.data.mongodb.port=27017
Tip | |
---|---|
If |
You can also declare your own Mongo
@Bean
if you want to take complete control of
establishing the MongoDB connection.
Spring Data Mongo provides a MongoTemplate
class that is very similar in its design to Spring’s JdbcTemplate
. As with
JdbcTemplate
Spring Boot auto-configures a bean for you to simply inject:
import org.springframework.beans.factory.annotation.Autowired; import org.springframework.data.mongodb.core.MongoTemplate; import org.springframework.stereotype.Component; @Component public class MyBean { private final MongoTemplate mongoTemplate; @Autowired public MyBean(MongoTemplate mongoTemplate) { this.mongoTemplate = mongoTemplate; } // ... }
See the MongoOperations
Javadoc for complete details.
Spring Data includes repository support for MongoDB. As with the JPA repositories discussed earlier, the basic principle is that queries are constructed for you automatically based on method names.
In fact, both Spring Data JPA and Spring Data MongoDB share the same common
infrastructure; so you could take the JPA example from earlier and, assuming that
City
is now a Mongo data class rather than a JPA @Entity
, it will work in the
same way.
package com.example.myapp.domain; import org.springframework.data.domain.*; import org.springframework.data.repository.*; public interface CityRepository extends Repository<City, Long> { Page<City> findAll(Pageable pageable); City findByNameAndCountryAllIgnoringCase(String name, String country); }
Tip | |
---|---|
For complete details of Spring Data MongoDB, including its rich object mapping technologies, refer to their reference documentation. |
Spring Boot provides a number of useful tools for testing your application. The
spring-boot-starter-test
POM provides Spring Test, JUnit, Hamcrest and Mockito
dependencies. There are also useful test utilities in the core spring-boot
module
under the org.springframework.boot.test
package.
If you use the
spring-boot-starter-test
“Starter POM” (in the test
scope
), you will find
the following provided libraries:
assertThat
style JUnit assertions.
These are common libraries that we generally find useful when writing tests. You are free to add additional test dependencies of your own if these don’t suit your needs.
One of the major advantages of dependency injection is that it should make your code
easier to unit test. You can simply instantiate objects using the new
operator without
even involving Spring. You can also use mock objects instead of real dependencies.
Often you need to move beyond “unit testing” and start “integration testing” (with
a Spring ApplicationContext
actually involved in the process). It’s useful to be able
to perform integration testing without requiring deployment of your application or
needing to connect to other infrastructure.
The Spring Framework includes a dedicated test module for just such integration testing.
You can declare a dependency directly to org.springframework:spring-test
or use the
spring-boot-starter-test
“Starter POM” to pull it in transitively.
If you have not used the spring-test
module before you should start by reading the
relevant section of the Spring Framework reference
documentation.
A Spring Boot application is just a Spring ApplicationContext
so nothing very special
has to be done to test it beyond what you would normally do with a vanilla Spring context.
One thing to watch out for though is that the external properties, logging and other
features of Spring Boot are only installed in the context by default if you use
SpringApplication
to create it.
Spring Boot provides a @SpringApplicationConfiguration
annotation as an alternative
to the standard spring-test
@ContextConfiguration
annotation. If you use
@SpringApplicationConfiguration
to configure the ApplicationContext
used in your
tests, it will be created via SpringApplication
and you will get the additional Spring
Boot features.
For example:
@RunWith(SpringJUnit4ClassRunner.class) @SpringApplicationConfiguration(classes = SampleDataJpaApplication.class) public class CityRepositoryIntegrationTests { @Autowired CityRepository repository; // ... }
Tip | |
---|---|
The context loader guesses whether you want to test a web application or not (e.g.
with |
If you want a web application to start up and listen on its normal port, so you can test
it with HTTP (e.g. using RestTemplate
), annotate your test class (or one of its
superclasses) with @IntegrationTest
. This can be very useful because it means you can
test the full stack of your application, but also inject its components into the test
class and use them to assert the internal state of the application after an HTTP
interaction. For Example:
@RunWith(SpringJUnit4ClassRunner.class) @SpringApplicationConfiguration(classes = SampleDataJpaApplication.class) @WebAppConfiguration @IntegrationTest public class CityRepositoryIntegrationTests { @Autowired CityRepository repository; RestTemplate restTemplate = new TestRestTemplate(); // ... interact with the running server }
Note | |
---|---|
Spring’s test framework will cache application contexts between tests. Therefore, as long as your tests share the same configuration, the time consuming process of starting and stopping the server will only happen once, regardless of the number of tests that actually run. |
To change the port you can add environment properties to @IntegrationTest
as colon- or
equals-separated name-value pairs, e.g. @IntegrationTest("server.port:9000")
.
Additionally you can set the server.port
and management.port
properties to 0
in order to run your integration tests using random ports. For example:
@RunWith(SpringJUnit4ClassRunner.class) @SpringApplicationConfiguration(classes = MyApplication.class) @WebAppConfiguration @IntegrationTest({"server.port=0", "management.port=0"}) public class SomeIntegrationTests { // ... }
See Section 55.4, “Discover the HTTP port at runtime” for a description of how you can discover the actual port that was allocated for the duration of the tests.
A few test utility classes are packaged as part of spring-boot
that are generally
useful when testing your application.
ConfigFileApplicationContextInitializer
is an ApplicationContextInitializer
that
can apply to your tests to load Spring Boot application.properties
files. You can use
this when you don’t need the full features provided by @SpringApplicationConfiguration
.
@ContextConfiguration(classes = Config.class, initializers = ConfigFileApplicationContextInitializer.class)
EnvironmentTestUtils
allows you to quickly add properties to a
ConfigurableEnvironment
or ConfigurableApplicationContext
. Simply call it with
key=value
strings:
EnvironmentTestUtils.addEnvironment(env, "org=Spring", "name=Boot");
OutputCapture
is a JUnit Rule
that you can use to capture System.out
and
System.err
output. Simply declare the capture as a @Rule
then use toString()
for assertions:
import org.junit.Rule; import org.junit.Test; import org.springframework.boot.test.OutputCapture; import static org.hamcrest.Matchers.*; import static org.junit.Assert.*; public class MyTest { @Rule public OutputCapture capture = new OutputCapture(); @Test public void testName() throws Exception { System.out.println("Hello World!"); assertThat(capture.toString(), containsString("World")); } }
TestRestTemplate
is a convenience subclass of Spring’s RestTemplate
that is
useful in integration tests. You can get a vanilla template or one that sends Basic HTTP
authentication (with a username and password). In either case the template will behave
in a test-friendly way: not following redirects (so you can assert the response
location), ignoring cookies (so the template is stateless), and not throwing exceptions
on server-side errors. It is recommended, but not mandatory, to use Apache HTTP Client
(version 4.3.2 or better), and if you have that on your classpath the TestRestTemplate
will respond by configuring the client appropriately.
public class MyTest { RestTemplate template = new TestRestTemplate(); @Test public void testRequest() throws Exception { HttpHeaders headers = template.getForEntity("http://myhost.com", String.class).getHeaders(); assertThat(headers.getLocation().toString(), containsString("myotherhost")); } }
If you work in a company that develops shared libraries, or if you work on an open-source or commercial library, you might want to develop your own auto-configuration. Auto-configuration classes can be bundled in external jars and still be picked-up by Spring Boot.
Under the hood, auto-configuration is implemented with standard @Configuration
classes.
Additional @Conditional
annotations are used to constrain when the auto-configuration
should apply. Usually auto-configuration classes use @ConditionalOnClass
and
@ConditionalOnMissingBean
annotations. This ensures that auto-configuration only
applies when relevant classes are found and when you have not declared your own
@Configuration
.
You can browse the source code of spring-boot-autoconfigure
to see the @Configuration
classes that we provide (see the META-INF/spring.factories
file).
Spring Boot checks for the presence of a META-INF/spring.factories
file within your
published jar. The file should list your configuration classes under the
EnableAutoConfiguration
key.
org.springframework.boot.autoconfigure.EnableAutoConfiguration=\ com.mycorp.libx.autoconfigure.LibXAutoConfiguration,\ com.mycorp.libx.autoconfigure.LibXWebAutoConfiguration
You can use the
@AutoConfigureAfter
or
@AutoConfigureBefore
annotations if your configuration needs to be applied in a specific order. For example,
if you provide web specific configuration, your class may need to be applied after
WebMvcAutoConfiguration
.
You almost always want to include one or more @Condition
annotations on your
auto-configuration class. The @ConditionalOnMissingBean
is one common example that is
used to allow developers to “override” auto-configuration if they are not happy with
your defaults.
Spring Boot includes a number of @Conditional
annotations that you can reuse in your own
code by annotating @Configuration
classes or individual @Bean
methods.
The @ConditionalOnClass
and @ConditionalOnMissingClass
annotations allows configuration
to be skipped based on the presence or absence of specific classes. Due to the fact that
annotation meta-data is parsed using ASM you can actually use the
value
attribute to refer to the real class, even though that class might not actually
appear on the running application classpath. You can also use the name
attribute if you
prefer to specify the class name using a String
value.
The @ConditionalOnBean
and @ConditionalOnMissingBean
annotations allow configurations
to be skipped based on the presence or absence of specific beans. You can use the value
attribute to specify beans by type, or name
to specify beans by name. The search
attribute allows you to limit the ApplicationContext
hierarchy that should be considered
when searching for beans.
Note | |
---|---|
|
The @ConditionalOnResource
annotation allows configuration to be included only when a
specific resource is present. Resources can be specified using the usual Spring
conventions, for example, file:/home/user/test.dat
.
The @ConditionalOnWebApplication
and @ConditionalOnNotWebApplication
annotations
allow configuration to be skipped depending on whether the application is a
web application. A web application is any application that is using a Spring
WebApplicationContext
, defines a session
scope or has a StandardServletEnvironment
.
The @ConditionalOnExpression
annotation allows configuration to be skipped based on the
result of a SpEL expression.
If you want to learn more about any of the classes discussed in this section you can check out the Spring Boot API documentation or you can browse the source code directly. If you have specific questions, take a look at the how-to section.
If you are comfortable with Spring Boot’s core features, you can carry on and read about production-ready features.
Spring Boot includes a number of additional features to help you monitor and manage your application when it’s pushed to production. You can choose to manage and monitor your application using HTTP endpoints, with JMX or even by remote shell (SSH or Telnet). Auditing, health and metrics gathering can be automatically applied to your application.
The spring-boot-actuator
module provides all of Spring Boot’s production-ready
features. The simplest way to enable the features is to add a dependency to the
spring-boot-starter-actuator
“Starter POM”.
To add the actuator to a Maven based project, add the following “starter” dependency:
<dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-actuator</artifactId> </dependency> </dependencies>
For Gradle, use the declaration:
dependencies {
compile("org.springframework.boot:spring-boot-starter-actuator")
}
Actuator endpoints allow you to monitor and interact with your application. Spring Boot
includes a number of built-in endpoints and you can also add your own. For example the
health
endpoint provides basic application health information.
The way that endpoints are exposed will depend on the type of technology that you choose.
Most applications choose HTTP monitoring, where the ID of the endpoint is mapped
to a URL. For example, by default, the health
endpoint will be mapped to /health
.
The following endpoints are available:
ID | Description | Sensitive |
---|---|---|
| Displays an auto-configuration report showing all auto-configuration candidates and the reason why they “were” or “were not” applied. | true |
| Displays a complete list of all the Spring Beans in your application. | true |
| Displays a collated list of all | true |
| Performs a thread dump. | true |
| Exposes properties from Spring’s | true |
| Shows application health information (defaulting to a simple “OK” message). | false |
| Displays arbitrary application info. | false |
| Shows “metrics” information for the current application. | true |
| Displays a collated list of all | true |
| Allows the application to be gracefully shutdown (not enabled by default). | true |
| Displays trace information (by default the last few HTTP requests). | true |
Note | |
---|---|
Depending on how an endpoint is exposed, the |
Endpoints can be customized using Spring properties. You can change if an endpoint is
enabled
, if it is considered sensitive
and even its id
.
For example, here is an application.properties
that changes the sensitivity and id
of the beans
endpoint and also enables shutdown
.
endpoints.beans.id=springbeans endpoints.beans.sensitive=false endpoints.shutdown.enabled=true
Note | |
---|---|
The prefix " |
The default information exposed by the health
endpoint is a simple “OK” message. It
is often useful to perform some additional health checks, for example you might check
that a database connection works, or that a remote REST endpoint is functioning.
To provide custom health information you can register a Spring bean that implements the
HealthIndicator
interface.
import org.springframework.boot.actuate.health.HealthIndicator; import org.springframework.stereotype.Component; @Component public class MyHealth implements HealthIndicator { @Override public Health health() { // perform some specific health check return ... } }
Spring Boot provides a
SimpleDatabaseHealthIndicator
implementation that attempts a simple database test as well as implementations for
Redis, MongoDB and RabbitMQ.
Spring Boot adds the HealthIndicator
instances automatically if beans of type DataSource
,
MongoTemplate
, RedisConnectionFactory
, RabbitTemplate
are present in the ApplicationContext
.
Besides implementing custom HealthIndicator`s and using out-of-box {sc-spring-boot-actuator}/health/Status.{sc-ext}[`Status
]
types, it is also possible to introduce custom Status
types for different or more complex system
states. In that case a custom implementation of the HealthAggregator
interface needs to be provided or the default implementation has to be configured using the
health.status.order
configuration property.
Assuming a new Status
with code FATAL
is being used in one of your HealthIndicator
implementations. To configure the severity or order add the following to your application properties:
health.status.order: FATAL, DOWN, UNKNOWN, UP
.
You can customize the data exposed by the info
endpoint by setting info.*
Spring
properties. All Environment
properties under the info key will be automatically
exposed. For example, you could add the following to your application.properties
:
info.app.name=MyService info.app.description=My awesome service info.app.version=1.0.0
If you are using Maven, you can automatically expand info properties from the Maven
project using resource filtering. In your pom.xml
you have (inside the <build/>
element):
<resources> <resource> <directory>src/main/resources</directory> <filtering>true</filtering> </resource> </resources>
You can then refer to your Maven “project properties” via placeholders, e.g.
project.artifactId=myproject project.name=Demo project.version=X.X.X.X project.description=Demo project for info endpoint info.build.artifact=${project.artifactId} info.build.name=${project.name} info.build.description=${project.description} info.build.version=${project.version}
Note | |
---|---|
In the above example we used |
Another useful feature of the info
endpoint is its ability to publish information
about the state of your git
source code repository when the project was built. If a
git.properties
file is contained in your jar the git.branch
and git.commit
properties will be loaded.
For Maven users the spring-boot-starter-parent
POM includes a pre-configured plugin to
generate a git.properties
file. Simply add the following declaration to your POM:
<build> <plugins> <plugin> <groupId>pl.project13.maven</groupId> <artifactId>git-commit-id-plugin</artifactId> </plugin> </plugins> </build>
A similar gradle-git
plugin is also available
for Gradle users, although a little more work is required to generate the properties file.
If you are developing a Spring MVC application, Spring Boot Actuator will auto-configure
all non-sensitive endpoints to be exposed over HTTP. The default convention is to use the
id
of the endpoint as the URL path. For example, health
is exposed as /health
.
If you use “Spring Security” sensitive endpoints will be exposed over HTTP, but also
protected. By default “basic” authentication will be used with the username user
and a generated password (which is printed on the console when the application starts).
Tip | |
---|---|
Generated passwords are logged as the application starts. Search for “Using default security password”. |
You can use Spring properties to change the username and password and to change the
security role required to access the endpoints. For example, you might set the following
in your application.properties
:
security.user.name=admin security.user.password=secret management.security.role=SUPERUSER
Sometimes it is useful to group all management endpoints under a single path. For example,
your application might already use /info
for another purpose. You can use the
management.contextPath
property to set a prefix for your management endpoint:
management.context-path=/manage
The application.properties
example above will change the endpoint from /{id}
to
/manage/{id}
(e.g. /manage/info
).
Exposing management endpoints using the default HTTP port is a sensible choice for cloud based deployments. If, however, your application runs inside your own data center you may prefer to expose endpoints using a different HTTP port.
The management.port
property can be used to change the HTTP port.
management.port=8081
Since your management port is often protected by a firewall, and not exposed to the public you might not need security on the management endpoints, even if your main application is secure. In that case you will have Spring Security on the classpath, and you can disable management security like this:
management.security.enabled=false
(If you don’t have Spring Security on the classpath then there is no need to explicitly disable the management security in this way, and it might even break the application.)
You can customize the address that the management endpoints are available on by
setting the management.address
property. This can be useful if you want to
listen only on an internal or ops-facing network, or to only listen for connections from
localhost
.
Note | |
---|---|
You can only listen on a different address if the port is different to the main server port. |
Here is an example application.properties
that will not allow remote management
connections:
management.port=8081 management.address=127.0.0.1
Java Management Extensions (JMX) provide a standard mechanism to monitor and manage
applications. By default Spring Boot will expose management endpoints as JMX MBeans
under the org.springframework.boot
domain.
The name of the MBean is usually generated from the id
of the endpoint. For example
the health
endpoint is exposed as org.springframework.boot/Endpoint/HealthEndpoint
.
If your application contains more than one Spring ApplicationContext
you may find that
names clash. To solve this problem you can set the endpoints.jmx.uniqueNames
property
to true
so that MBean names are always unique.
You can also customize the JMX domain under which endpoints are exposed. Here is an
example application.properties
:
endpoints.jmx.domain=myapp endpoints.jmx.uniqueNames=true
If you don’t want to expose endpoints over JMX you can set the spring.jmx.enabled
property to false
:
spring.jmx.enabled=false
Jolokia is a JMX-HTTP bridge giving an alternative method of accessing JMX beans. To
use Jolokia, simply include a dependency to org.jolokia:jolokia-core
. For example,
using Maven you would add the following:
<dependency> <groupId>org.jolokia</groupId> <artifactId>jolokia-core</artifactId> </dependency>
Jolokia can then be accessed using /jolokia
on your management HTTP server.
Jolokia has a number of settings that you would traditionally configure using servlet
parameters. With Spring Boot you can use your application.properties
, simply prefix the
parameter with jolokia.config.
:
jolokia.config.debug=true
Spring Boot supports an integrated Java shell called “CRaSH”. You can use CRaSH to
ssh
or telnet
into your running application. To enable remote shell support add a
dependency to spring-boot-starter-remote-shell
:
<dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-remote-shell</artifactId> </dependency>
Tip | |
---|---|
If you want to also enable telnet access your will additionally need a dependency
on |
By default the remote shell will listen for connections on port 2000
. The default user
is user
and the default password will be randomly generated and displayed in the log
output. If your application is using Spring Security, the shell will use
the same configuration by default. If not, a simple
authentication will be applied and you should see a message like this:
Using default password for shell access: ec03e16c-4cf4-49ee-b745-7c8255c1dd7e
Linux and OSX users can use ssh
to connect to the remote shell, Windows users can
download and install PuTTY.
$ ssh -p 2000 user@localhost user@localhost's password: . ____ _ __ _ _ /\\ / ___'_ __ _ _(_)_ __ __ _ \ \ \ \ ( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \ \\/ ___)| |_)| | | | | || (_| | ) ) ) ) ' |____| .__|_| |_|_| |_\__, | / / / / =========|_|==============|___/=/_/_/_/ :: Spring Boot :: (v1.1.0.RC1) on myhost
Type help
for a list of commands. Spring boot provides metrics
, beans
, autoconfig
and endpoint
commands.
You can use the shell.auth.simple.username
and shell.auth.simple.password
properties
to configure custom connection credentials. It is also possible to use a
“Spring Security” AuthenticationManager
to handle login duties. See the
CrshAutoConfiguration
and ShellProperties
Javadoc for full details.
The remote shell can be extended in a number of interesting ways.
You can write additional shell commands using Groovy or Java (see the CRaSH documentation for details). By default Spring Boot will search for commands in the following locations:
classpath*:/commands/**
classpath*:/crash/commands/**
Tip | |
---|---|
You can change the search path by settings a |
Here is a simple “hello world” command that could be loaded from
src/main/resources/commands/hello.groovy
package commands import org.crsh.cli.Usage import org.crsh.cli.Command class hello { @Usage("Say Hello") @Command def main(InvocationContext context) { return "Hello" } }
Spring Boot adds some additional attributes to InvocationContext
that you can access
from your command:
Attribute Name | Description |
---|---|
| The version of Spring Boot |
| The version of the core Spring Framework |
| Access to the Spring |
| Access to the Spring |
In addition to new commands, it is also possible to extend other CRaSH shell features.
All Spring Beans that extends org.crsh.plugin.CRaSHPlugin
will be automatically
registered with the shell.
For more information please refer to the CRaSH reference documentation.
Spring Boot Actuator includes a metrics service with “gauge” and “counter” support.
A “gauge” records a single value; and a “counter” records a delta (an increment or
decrement). Metrics for all HTTP requests are automatically recorded, so if you hit the
metrics
endpoint should should see a response similar to this:
{ "counter.status.200.root": 20, "counter.status.200.metrics": 3, "counter.status.401.root": 4, "gauge.response.root": 2, "gauge.response.metrics": 3, "classes": 5808, "classes.loaded": 5808, "classes.unloaded": 0, "heap": 3728384, "heap.committed": 986624, "heap.init": 262144, "heap.used": 52765, "mem": 986624, "mem.free": 933858, "processors": 8, "threads": 15, "threads.daemon": 11, "threads.peak": 15, "uptime": 494836 }
Here we can see basic memory
, heap
, class loading
, processor
and thread pool
information along with some HTTP metrics. In this instance the root
(“/”) and /metrics
URLs have returned HTTP 200
responses 20
and 3
times respectively. It also appears
that the root
URL returned HTTP 401
(unauthorized) 4
times.
The gauge
shows the last response time for a request. So the last request to root
took
2ms
to respond and the last to /metrics
took 3ms
.
Note | |
---|---|
In this example we are actually accessing the endpoint over HTTP using the
|
To record your own metrics inject a
CounterService
and/or
GaugeService
into
your bean. The CounterService
exposes increment
, decrement
and reset
methods; the
GaugeService
provides a submit
method.
Here is a simple example that counts the number of times that a method is invoked:
import org.springframework.beans.factory.annotation.Autowired; import org.springframework.boot.actuate.metrics.CounterService; import org.springframework.stereotype.Service; @Service public class MyService { private final CounterService counterService; @Autowired public MyService(CounterService counterService) { this.counterService = counterService; } public void exampleMethod() { this.counterService.increment("services.system.myservice.invoked"); } }
Tip | |
---|---|
You can use any string as a metric name but you should follow guidelines of your chosen store/graphing technology. Some good guidelines for Graphite are available on Matt Aimonetti’s Blog. |
Metric service implementations are usually bound to a
MetricRepository
.
A MetricRepository
is responsible for storing and retrieving metric information. Spring
Boot provides an InMemoryMetricRepository
and a RedisMetricRepository
out of the
box (the in-memory repository is the default) but you can also write your own. The
MetricRepository
interface is actually composed of higher level MetricReader
and
MetricWriter
interfaces. For full details refer to the
Javadoc.
There’s nothing to stop you hooking a MetricRepository
with back-end storage directly
into your app, but we recommend using the default InMemoryMetricRepository
(possibly with a custom Map
instance if you are worried about heap usage) and
populating a back-end repository through a scheduled export job. In that way you get
some buffering in memory of the metric values and you can reduce the network
chatter by exporting less frequently or in batches. Spring Boot provides
an Exporter
interface and a few basic implementations for you to get started with that.
User of the Coda Hale “Metrics” library will automatically
find that Spring Boot metrics are published to com.codahale.metrics.MetricRegistry
. A
default com.codahale.metrics.MetricRegistry
Spring bean will be created when you declare
a dependency to the com.codahale.metrics:metrics-core
library; you can also register you
own @Bean
instance if you need customizations.
Users can create Coda Hale metrics by prefixing their metric names with the appropriate
type (e.g. histogram.*
, meter.*
).
If the “Spring Messaging” jar is on your classpath a MessageChannel
called
metricsChannel
is automatically created (unless one already exists). All metric update
events are additionally published as “messages” on that channel. Additional analysis or
actions can be taken by clients subscribing to that channel.
Spring Boot Actuator has a flexible audit framework that will publish events once Spring Security is in play (“authentication success”, “failure” and “access denied” exceptions by default). This can be very useful for reporting, and also to implement a lock-out policy based on authentication failures.
You can also choose to use the audit services for your own business events. To do that
you can either inject the existing AuditEventRepository
into your own components and
use that directly, or you can simply publish AuditApplicationEvent
via the Spring
ApplicationEventPublisher
(using ApplicationEventPublisherAware
).
Tracing is automatically enabled for all HTTP requests. You can view the trace
endpoint
and obtain basic information about the last few requests:
[{ "timestamp": 1394343677415, "info": { "method": "GET", "path": "/trace", "headers": { "request": { "Accept": "text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8", "Connection": "keep-alive", "Accept-Encoding": "gzip, deflate", "User-Agent": "Mozilla/5.0 Gecko/Firefox", "Accept-Language": "en-US,en;q=0.5", "Cookie": "_ga=GA1.1.827067509.1390890128; ..." "Authorization": "Basic ...", "Host": "localhost:8080" }, "response": { "Strict-Transport-Security": "max-age=31536000 ; includeSubDomains", "X-Application-Context": "application:8080", "Content-Type": "application/json;charset=UTF-8", "status": "200" } } } },{ "timestamp": 1394343684465, ... }]
If you need to trace additional events you can inject a
TraceRepository
into your
Spring Beans. The add
method accepts a single Map
structure that will be converted to
JSON and logged.
By default an InMemoryTraceRepository
will be used that stores the last 100 events. You
can define your own instance of the InMemoryTraceRepository
bean if you need to expand
the capacity. You can also create your own alternative TraceRepository
implementation
if needed.
In Spring Boot Actuator you can find ApplicationPidListener
which creates file
containing application PID (by default in application directory and file name is
application.pid
). It’s not activated by default, but you can do it in two simple
ways described below.
In META-INF/spring.factories
file you have to activate the listener:
org.springframework.context.ApplicationListener=\ org.springframework.boot.actuate.system.ApplicationPidListener
If you want to explore some of the concepts discussed in this chapter, you can take a look at the actuator sample applications. You also might want to read about graphing tools such as Graphite.
Otherwise, you can continue on, to read about “cloud deployment options” or jump ahead for some in depth information about Spring Boot’s build tool plugins.
Spring Boot’s executable jars are ready-made for most popular cloud PaaS (platform-as-a-service) providers. These providers tend to require that you `bring your own container'; they manage application processes (not Java applications specifically), so they need some intermediary layer that adapts your application to the cloud’s notion of a running process.
Two popular cloud providers, Heroku and Cloud Foundry, employ a “buildpack” approach.
The buildpack wraps your deployed code in whatever is needed to start your
application: it might be a JDK and a call to java
, it might be an embedded webserver,
or it might be a full fledged application server. A buildpack is pluggable, but ideally
you should be able to get by with as few customizations to it as possible.
This reduces the footprint of functionality that is not under your control. It minimizes
divergence between deployment and production environments.
Ideally, your application, like a Spring Boot executable jar, has everything that it needs to run packaged within it.
In this section we’ll look at what it takes to get the simple application that we developed in the “Getting Started” section up and running in the Cloud.
Cloud Foundry provides default buildpacks that come into play if no other buildpack is
specified. The Cloud Foundry Java buildpack
has excellent support for Spring applications, including Spring Boot. You can deploy
stand-alone executable jar applications, as well as traditional .war
packaged
applications.
Once you’ve built your application (using, for example, mvn clean package
) and
installed the cf
command line tool, simply deploy your application using the cf push
command as follows,
substituting the path to your compiled .jar
. Be sure to have
logged in with your
cf
command line client before pushing an application.
$ cf push acloudyspringtime -p target/demo-0.0.1-SNAPSHOT.jar
See the cf push
documentation for more options. If there is a Cloud Foundry
manifest.yml
file present in the same directory, it will be consulted.
Note | |
---|---|
Here we are substituting |
At this point cf
will start uploading your application:
Uploading acloudyspringtime... OK Preparing to start acloudyspringtime... OK -----> Downloaded app package (8.9M) -----> Java Buildpack source: system -----> Downloading Open JDK 1.7.0_51 from .../x86_64/openjdk-1.7.0_51.tar.gz (1.8s) Expanding Open JDK to .java-buildpack/open_jdk (1.2s) -----> Downloading Spring Auto Reconfiguration from 0.8.7 .../auto-reconfiguration-0.8.7.jar (0.1s) -----> Uploading droplet (44M) Checking status of app acloudyspringtime... 0 of 1 instances running (1 starting) ... 0 of 1 instances running (1 down) ... 0 of 1 instances running (1 starting) ... 1 of 1 instances running (1 running) App started
Congratulations! The application is now live!
It’s easy to then verify the status of the deployed application:
$ cf apps Getting applications in ... OK name requested state instances memory disk urls ... acloudyspringtime started 1/1 512M 1G acloudyspringtime.cfapps.io ...
Once Cloud Foundry acknowledges that your application has been deployed, you should be
able to hit the application at the URI given, in this case
http://acloudyspringtime.cfapps.io/
.
By default, meta-data about the running application as well as service connection
information is exposed to the application as environment variables (for example:
$VCAP_SERVICES
). This architecture decision is due to Cloud Foundry’s polyglot
(any language and platform can be supported as a buildpack) nature; process-scoped
environment variables are language agnostic.
Environment variables don’t always make for the easiest API so Spring Boot automatically
extracts them and flattens the data into properties that can be accessed through
Spring’s Environment
abstraction:
@Component class MyBean implements EnvironmentAware { private String instanceId; @Override public void setEnvironment(Environment environment) { this.instanceId = environment.getProperty("vcap.application.instance_id"); } // ... }
All Cloud Foundry properties are prefixed with vcap
. You can use vcap properties to
access application information (such as the public URL of the application) and service
information (such as database credentials). See VcapApplicationListener
Javdoc for
complete details.
Tip | |
---|---|
The Spring Cloud project is a better fit for tasks such as configuring a DataSource; it also lets you use Spring Cloud with Heroku. |
Heroku is another popular PaaS platform. To customize Heroku builds, you provide a
Procfile
, which provides the incantation required to deploy an application. Heroku
assigns a port
for the Java application to use and then ensures that routing to the
external URI works.
You must configure your application to listen on the correct port. Here’s the Procfile
for our starter REST application:
web: java -Dserver.port=$PORT -jar target/demo-0.0.1-SNAPSHOT.jar
Spring Boot makes -D
arguments available as properties accessible from a Spring
Environment
instance. The server.port
configuration property is fed to the embedded
Tomcat or Jetty instance which then uses it when it starts up. The $PORT
environment
variable is assigned to us by the Heroku PaaS.
Heroku by default will use Java 1.6. This is fine as long as your Maven or Gradle build
is set to use the same version (Maven users can use the java.version
property). If you
want to use JDK 1.7, create a new file adjacent to your pom.xml
and Procfile
,
called system.properties
. In this file add the following:
java.runtime.version=1.7
This should be everything you need. The most common workflow for Heroku deployments is to
git push
the code to production.
$ git push heroku master Initializing repository, done. Counting objects: 95, done. Delta compression using up to 8 threads. Compressing objects: 100% (78/78), done. Writing objects: 100% (95/95), 8.66 MiB | 606.00 KiB/s, done. Total 95 (delta 31), reused 0 (delta 0) -----> Java app detected -----> Installing OpenJDK 1.7... done -----> Installing Maven 3.0.3... done -----> Installing settings.xml... done -----> executing /app/tmp/cache/.maven/bin/mvn -B -Duser.home=/tmp/build_0c35a5d2-a067-4abc-a232-14b1fb7a8229 -Dmaven.repo.local=/app/tmp/cache/.m2/repository -s /app/tmp/cache/.m2/settings.xml -DskipTests=true clean install [INFO] Scanning for projects... Downloading: http://repo.spring.io/... Downloaded: http://repo.spring.io/... (818 B at 1.8 KB/sec) .... Downloaded: http://s3pository.heroku.com/jvm/... (152 KB at 595.3 KB/sec) [INFO] Installing /tmp/build_0c35a5d2-a067-4abc-a232-14b1fb7a8229/target/... [INFO] Installing /tmp/build_0c35a5d2-a067-4abc-a232-14b1fb7a8229/pom.xml ... [INFO] ------------------------------------------------------------------------ [INFO] BUILD SUCCESS [INFO] ------------------------------------------------------------------------ [INFO] Total time: 59.358s [INFO] Finished at: Fri Mar 07 07:28:25 UTC 2014 [INFO] Final Memory: 20M/493M [INFO] ------------------------------------------------------------------------ -----> Discovering process types Procfile declares types -> web -----> Compressing... done, 70.4MB -----> Launching... done, v6 http://agile-sierra-1405.herokuapp.com/ deployed to Heroku To [email protected]:agile-sierra-1405.git * [new branch] master -> master
Your application should now be up and running on Heroku.
CloudBees provides cloud-based “continuous integration” and “continuous delivery” services as well as Java PaaS hosting. Sean Gilligan has contributed an excellent Spring Boot sample application to the CloudBees community GitHub repository. The project includes an extensive README that covers the steps that you need to follow when deploying to CloudBees.
Check out the Cloud Foundry, Heroku and CloudBees web sites for more information about the kinds of features that a PaaS can offer. These are just three of the most popular Java PaaS providers, since Spring Boot is so amenable to cloud-based deployment you’re free to consider other providers as well.
The next section goes on to cover the Spring Boot CLI; or you can jump ahead to read about build tool plugins.
The Spring Boot CLI is a command line tool that can be used if you want to quickly prototype with Spring. It allows you to run Groovy scripts, which means that you have a familiar Java-like syntax, without so much boilerplate code.
The Spring Boot CLI can be installed manually; using GVM (the Groovy Environment Manually) or using Homebrew if you are an OSX user. See Section 9.2, “Installing the Spring Boot CLI” in the “Getting started” section for comprehensive installation instructions.
Once you have installed the CLI you can run it by typing spring
. If you run spring
without any arguments, a simple help screen is displayed:
$ spring
usage: spring [--help] [--version]
<command> [<args>]
Available commands are:
run [options] <files> [--] [args]
Run a spring groovy script
... more command help is shown here
You can use help
to get more details about any of the supported commands. For example:
$ spring help run spring run - Run a spring groovy script usage: spring run [options] <files> [--] [args] Option Description ------ ----------- --autoconfigure [Boolean] Add autoconfigure compiler transformations (default: true) --classpath, -cp Additional classpath entries -e, --edit Open the file with the default system editor --no-guess-dependencies Do not attempt to guess dependencies --no-guess-imports Do not attempt to guess imports -q, --quiet Quiet logging -v, --verbose Verbose logging of dependency resolution --watch Watch the specified file for changes
The version
command provides a quick way to check which version of Spring Boot you are
using.
$ spring version Spring CLI v1.1.0.RC1
You can compile and run Groovy source code using the run
command. The Spring Boot CLI
is completely self contained so you don’t need any external Groovy installation.
Here is an example “hello world” web application written in Groovy:
@RestController class WebApplication { @RequestMapping("/") String home() { "Hello World!" } }
Standard Groovy includes a @Grab
annotation which allows you to declare dependencies
on a third-party libraries. This useful technique allows Groovy to download jars in the
same way as Maven or Gradle would; but without requiring you to use a build tool.
Spring Boot extends this technique further, and will attempt to deduce which libraries
to “grab” based on your code. For example, since the WebApplication
code above uses
@RestController
annotations, “Tomcat” and “Spring MVC” will be grabbed.
The following items are used as “grab hints”:
Items | Grabs |
---|---|
| JDBC Application. |
| JMS Application. |
| JUnit. |
| RabbitMQ. |
| Project Reactor. |
extends | Spock test. |
| Spring Batch. |
| Spring Integration. |
| Spring Mobile. |
| Spring MVC + Embedded Tomcat. |
| Spring Security. |
| Spring Transaction Management. |
Tip | |
---|---|
See subclasses of
|
Spring Boot extends Groovy’s standard @Grab
support by allowing you to specify a dependency
without a group or version, for example @Grab('freemarker')
. This will consult Spring Boot’s
default dependency metadata to deduce the artifact’s group and version. Note that the default
metadata is tied to the version of the CLI that you’re using – it will only change when you move
to a new version of the CLI, putting you in control of when the versions of your dependencies
may change. A table showing the dependencies and their versions that are included in the default
metadata can be found in the appendix.
Spring Boot provides a new annotation, @GrabMetadata
that can be used to provide custom
dependency metadata that overrides Spring Boot’s defaults. This metadata is specified by
using the new annotation to provide the coordinates of one or more properties files. For example `
@GrabMetadata([com.example:versions-one:1.0.0, com.example.versions-two:1.0.0]). The
properties files are applied in the order that their specified. In the example above, this means
that properties in `versions-two
will override properties in versions-one
. Each entry in
each properties file must be in the form group:module=version
. You can use @GrabVersions
anywhere that you can use @Grab
, however, to ensure consistent ordering of the metadata, you
can only use @GrabVersions
at most once in your application.
To help reduce the size of your Groovy code, several import
statements are
automatically included. Notice how the example above refers to @Component
,
@RestController
and @RequestMapping
without needing to use
fully-qualified names or import
statements.
Tip | |
---|---|
Many Spring annotations will work without using |
The test
command allows you to compile and run tests for your application. Typical
usage looks like this:
$ spring test app.groovy tests.groovy Total: 1, Success: 1, : Failures: 0 Passed? true
In this example, tests.groovy
contains JUnit @Test
methods or Spock Specification
classes. All the common framework annotations and static methods should be available to
you without having to import
them.
Here is the test.groovy
file that we used above (with a JUnit test):
class ApplicationTests { @Test void homeSaysHello() { assertEquals("Hello World", new WebApplication().home()) } }
Tip | |
---|---|
If you have more than one test source files, you might prefer to organize them
into a |
You can use “shell globbing” with all commands that accept file input. This allows you to easily use multiple files from a single directory, e.g.
$ spring run *.groovy
This technique can also be useful if you want to segregate your “test” or “spec” code from the main application code:
$ spring test app/*.groovy test/*.groovy
You can use the jar
command to package your application into a self-contained
executable jar file. For example:
$ spring jar my-app.jar *.groovy
The resulting jar will contain the classes produced by compiling the application and all
of the application’s dependencies so that it can then be run using java -jar
. The jar
file will also contain entries from the application’s classpath.
See the output of spring help jar
for more information.
Spring Boot includes command-line completion scripts for BASH and zsh shells. If you
don’t use either of these shells (perhaps you are a Windows user) then you can use the
shell
command to launch an integrated shell.
$ spring shell
Spring Boot (v1.1.0.RC1)
Hit TAB to complete. Type 'help' and hit RETURN for help, and 'exit' to quit.
From inside the embedded shell you can run other commands directly:
$ version Spring CLI v1.1.0.RC1
The embedded shell supports ANSI color output as well as tab
completion. If you need
to run a native command you can use the $
prefix. Hitting ctrl-c
will exit the
embedded shell.
Spring Framework 4.0 has native support for a beans{}
“DSL” (borrowed from
Grails), and you can embed bean definitions in your Groovy
application scripts using the same format. This is sometimes a good way to include
external features like middleware declarations. For example:
@Configuration class Application implements CommandLineRunner { @Autowired SharedService service @Override void run(String... args) { println service.message } } import my.company.SharedService beans { service(SharedService) { message "Hello World" } }
You can mix class declarations with beans{}
in the same file as long as they stay at
the top level, or you can put the beans DSL in a separate file if you prefer.
There are some sample groovy scripts available from the GitHub repository that you can use to try out the Spring Boot CLI. There is also extensive javadoc throughout the source code.
If you find that you reach the limit of the CLI tool, you will probably want to look at converting your application to full Gradle or Maven built “groovy project”. The next section covers Spring Boot’s Build tool plugins that you can use with Gradle or Maven.
Spring Boot provides build tool plugins for Maven and Gradle. The plugins offer a variety of features, including the packaging of executable jars. This section provides more details on both plugins, as well as some help should you need to extend an unsupported build system. If you are just getting started, you might want to read “Chapter 12, Build systems” from the Part III, “Using Spring Boot” section first.
The Spring Boot Maven Plugin provides Spring Boot support in Maven, allowing you to package executable jar or war archives and run an application “in-place”. To use it you must be using Maven 3 (or better).
Note | |
---|---|
Refer to the Spring Boot Maven Plugin Site for complete plugin documentation. |
To use the Spring Boot Maven Plugin simply include the appropriate XML in the plugins
section of your pom.xml
<?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <!-- ... --> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> <version>1.1.0.RC1</version> <executions> <execution> <goals> <goal>repackage</goal> </goals> </execution> </executions> </plugin> </plugins> </build> </project>
This configuration will repackage a jar or war that is built during the package
phase of
the Maven lifecycle. The following example shows both the repackaged jar, as well as the
original jar, in the target
directory:
$ mvn package $ ls target/*.jar target/myproject-1.0.0.jar target/myproject-1.0.0.jar.original
If you don’t include the <execution/>
configuration as above, you can run the plugin on
its own (but only if the package goal is used as well). For example:
$ mvn package spring-boot:repackage $ ls target/*.jar target/myproject-1.0.0.jar target/myproject-1.0.0.jar.original
If you are using a milestone or snapshot release you will also need to add appropriate
pluginRepository
elements:
<pluginRepositories> <pluginRepository> <id>spring-snapshots</id> <url>http://repo.spring.io/snapshot</url> </pluginRepository> <pluginRepository> <id>spring-milestones</id> <url>http://repo.spring.io/milestone</url> </pluginRepository> </pluginRepositories>
Once spring-boot-maven-plugin
has been included in your pom.xml
it will automatically
attempt to rewrite archives to make them executable using the spring-boot:repackage
goal. You should configure your project to build a jar or war (as appropriate) using the
usual packaging
element:
<?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> <!-- ... --> <packaging>jar</packaging> <!-- ... --> </project>
Your existing archive will be enhanced by Spring Boot during the package
phase. The
main class that you want to launch can either be specified using a configuration option,
or by adding a Main-Class
attribute to the manifest in the usual way. If you don’t
specify a main class the plugin will search for a class with a
public static void main(String[] args)
method.
To build and run a project artifact, you can type the following:
$ mvn package $ java -jar target/mymodule-0.0.1-SNAPSHOT.jar
To build a war file that is both executable and deployable into an external container you need to mark the embedded container dependencies as “provided”, e.g:
<?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> <!-- ... --> <packaging>war</packaging> <!-- ... --> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-tomcat</artifactId> <scope>provided</scope> </dependency> <!-- ... --> </dependencies> </project>
Advanced configuration options and examples are available in the plugin info page.
The Spring Boot Gradle Plugin provides Spring Boot support in Gradle, allowing you to
package executable jar or war archives, run Spring Boot applications and omit version
information from your build.gradle
file for “blessed” dependencies.
To use the Spring Boot Gradle Plugin simply include a buildscript
dependency and apply
the spring-boot
plugin:
buildscript { dependencies { classpath("org.springframework.boot:spring-boot-gradle-plugin:1.1.0.RC1") } } apply plugin: 'spring-boot'
If you are using a milestone or snapshot release you will also need to add appropriate
repositories
reference:
buildscript { repositories { maven.url "http://repo.spring.io/snapshot" maven.url "http://repo.spring.io/milestone" } // ... }
The spring-boot
plugin will register a custom Gradle ResolutionStrategy
with your
build that allows you to omit version numbers when declaring dependencies to “blessed”
artifacts. To make use of this functionality, simply declare dependencies in the usual way,
but leave the version number empty:
dependencies { compile("org.springframework.boot:spring-boot-starter-web") compile("org.thymeleaf:thymeleaf-spring4") compile("nz.net.ultraq.thymeleaf:thymeleaf-layout-dialect") }
Note | |
---|---|
The version of the |
The spring-boot
plugin will only supply a version where one is not specified. To
use a version of an artifact that differs from the one that the plugin would provide,
simply specify the version when you declare the dependency as you usually would. For
example:
dependencies {
compile("org.thymeleaf:thymeleaf-spring4:2.1.1.RELEASE")
}
If is possible to customize the versions used by the ResolutionStrategy
if you need
to deviate from Spring Boot’s “blessed” dependencies. Alternative version meta-data
is consulted using the versionManagement
configuration. For example:
dependencies { versionManagement("com.mycorp:mycorp-versions:1.0.0.RELEASE@properties") compile("org.springframework.data:spring-data-hadoop") }
Version information needs to be published to a repository as a .properties
file. For
the above example mycorp-versions.properties
file might contain the following:
org.springframework.data\:spring-data-hadoop=2.0.0.RELEASE
The properties file takes precedence over Spring Boot’s defaults, and can be used to override version numbers if necessary.
Once the spring-boot
plugin has been applied to your project it will automatically
attempt to rewrite archives to make them executable using the bootRepackage
task. You
should configure your project to build a jar or war (as appropriate) in the usual way.
The main class that you want to launch can either be specified using a configuration
option, or by adding a Main-Class
attribute to the manifest. If you don’t specify a
main class the plugin will search for a class with a
public static void main(String[] args)
method.
To build and run a project artifact, you can type the following:
$ gradle build $ java -jar build/libs/mymodule-0.0.1-SNAPSHOT.jar
To build a war file that is both executable and deployable into an external container, you need to mark the embedded container dependencies as belonging to a configuration named "providedRuntime", e.g:
... apply plugin: 'war' war { baseName = 'myapp' version = '0.5.0' } repositories { mavenCentral() maven { url "http://repo.spring.io/libs-snapshot" } } configurations { providedRuntime } dependencies { compile("org.springframework.boot:spring-boot-starter-web") providedRuntime("org.springframework.boot:spring-boot-starter-tomcat") ... }
To run a project in place without building a jar first you can use the "bootRun" task:
$ gradle bootRun
Running this way makes your static classpath resources (i.e. in src/main/resources
by
default) reloadable in the live application, which can be helpful at development time.
The gradle plugin automatically extends your build script DSL with a springBoot
element
for configuration. Simply set the appropriate properties as you would with any other Gradle
extension (see below for a list of configuration options):
springBoot { backupSource = false }
Sometimes it may be more appropriate to not package default dependencies resolved from
compile
, runtime
and provided
scopes. If the created executable jar file
is intended to be run as it is, you need to have all dependencies nested inside it;
however, if the plan is to explode a jar file and run the main class manually, you may already
have some of the libraries available via CLASSPATH
. This is a situation where
you can repackage your jar with a different set of dependencies.
Using a custom
configuration will automatically disable dependency resolving from
compile
, runtime
and provided
scopes. Custom configuration can be either
defined globally (inside the springBoot
section) or per task.
task clientJar(type: Jar) { appendix = 'client' from sourceSets.main.output exclude('**/*Something*') } task clientBoot(type: BootRepackage, dependsOn: clientJar) { withJarTask = clientJar customConfiguration = "mycustomconfiguration" }
In above example, we created a new clientJar
Jar task to package a customized
file set from your compiled sources. Then we created a new clientBoot
BootRepackage task and instructed it to work with only clientJar
task and
mycustomconfiguration
.
configurations {
mycustomconfiguration.exclude group: 'log4j'
}
dependencies {
mycustomconfiguration configurations.runtime
}
The configuration that we are referring to in BootRepackage
is a normal
Gradle
configuration. In the above example we created a new configuration named
mycustomconfiguration
instructing it to derive from a runtime
and exclude the log4j
group. If the clientBoot
task is executed, the repackaged boot jar will have all
dependencies from runtime
but no log4j
jars.
The following configuration options are available:
Name | Description |
---|---|
| The main class that should be run. If not specified the |
| The name of the provided configuration (defaults to |
| If the original source archive should be backed-up before being repackaged (defaults
to |
| The name of the custom configuration. |
| The type of archive, corresponding to how the dependencies are laid out inside (defaults to a guess based on the archive type). |
When spring-boot
is applied to your Gradle project a default task named bootRepackage
is created automatically. The bootRepackage
task depends on Gradle assemble
task, and
when executed, it tries to find all jar artifacts whose qualifier is empty (i.e. tests and
sources jars are automatically skipped).
Due to the fact that bootRepackage
finds all created jar artifacts, the order of
Gradle task execution is important. Most projects only create a single jar file, so
usually this is not an issue; however, if you are planning to create a more complex
project setup, with custom Jar
and BootRepackage
tasks, there are few tweaks to
consider.
If you are just creating custom jar files from your project you can simply disables
default jar
and bootRepackage
tasks:
jar.enabled = false bootRepackage.enabled = false
Another option is to instruct the default bootRepackage
task to only work with a
default jar
task.
bootRepackage.withJarTask = jar
If you have a default project setup where the main jar file is created and repackaged,
and you still want to create additional custom jars, you can combine your custom
repackage tasks together and use dependsOn
so that the bootJars
task will run after
the default bootRepackage
task is executed:
task bootJars bootJars.dependsOn = [clientBoot1,clientBoot2,clientBoot3] build.dependsOn(bootJars)
All the above tweaks are usually used to avoid situations where an already created boot jar is repackaged again. Repackaging an existing boot jar will not break anything, but you may find that it includes unnecessary dependencies.
If you want to use a build tool other than Maven or Gradle, you will likely need to develop your own plugin. Executable jars need to follow a specific format and certain entries need to be written in an uncompressed form (see the executable jar format section in the appendix for details).
The Spring Boot Maven and Gradle plugins both make use of spring-boot-loader-tools
to
actually generate jars. You are also free to use this library directly yourself if you
need to.
To repackage an existing archive so that it becomes a self-contained executable archive
use org.springframework.boot.loader.tools.Repackager
. The Repackager
class takes a
single constructor argument that refers to an existing jar or war archive. Use one of the
two available repackage()
methods to either replace the original file or write to a new
destination. Various settings can also be configured on the repackager before it is
run.
When repackaging an archive you can include references to dependency files using the
org.springframework.boot.loader.tools.Libraries
interface. We don’t provide any
concrete implementations of Libraries
here as they are usually build system specific.
If your archive already includes libraries you can use Libraries.NONE
.
If you don’t use Repackager.setMainClass()
to specify a main class, the repackager will
use ASM to read class files and attempt to find a suitable class
with a public static void main(String[] args)
method. An exception is thrown if more
than one candidate is found.
Here is a typical example repackage:
Repackager repackager = new Repackager(sourceJarFile); repackager.setBackupSource(false); repackager.repackage(new Libraries() { @Override public void doWithLibraries(LibraryCallback callback) throws IOException { // Build system specific implementation, callback for each dependency // callback.library(nestedFile, LibraryScope.COMPILE); } });
If you’re interested in how the build tool plugins work you can
look at the spring-boot-tools
module on GitHub. More
technical details of the executable
jar format are covered in the appendix.
If you have specific build-related questions you can check out the ‘how-to’ guides.
This section provides answers to some common “how do I do that…” type of questions that often arise when using Spring Boot. This is by no means an exhaustive list, but it does cover quite a lot.
If you are having a specific problem that we don’t cover here, you might want to check out
stackoverflow.com to see if someone has
already provided an answer; this is also a great place to ask new questions (please use
the spring-boot
tag).
We’re also more than happy to extend this section; If you want to add a “how-to” you can send us a pull request.
The Spring Boot auto-configuration tries its best to “do the right thing”, but sometimes things fail and it can be hard to tell why.
There is a really useful AutoConfigurationReport
available in any Spring Boot
ApplicationContext
. You will see it if you enable DEBUG
logging output. If you use
the spring-boot-actuator
there is also an autoconfig
endpoint that renders the report
in JSON. Use that to debug the application and see what features have been added (and
which not) by Spring Boot at runtime.
Many more questions can be answered by looking at the source code and the javadoc. Some rules of thumb:
*AutoConfiguration
and read their sources, in particular the
@Conditional*
annotations to find out what features they enable and when. Add
--debug
to the command line or a System property -Ddebug
to get a log on the
console of all the autoconfiguration decisions that were made in your app. In a running
Actuator app look at the autoconfig
endpoint (‘/autoconfig’ or the JMX equivalent) for
the same information.
@ConfigurationProperties
(e.g.
ServerProperties
)
and read from there the available external configuration options. The
@ConfigurationProperties
has a name
attribute which acts as a prefix to external
properties, thus ServerProperties
has prefix="server"
and its configuration properties
are server.port
, server.address
etc. In a running Actuator app look at the
configprops
endpoint.
RelaxedEnvironment
to pull configuration values explicitly out of the
Environment
. It often is used with a prefix.
@Value
annotations that bind directly to the Environment
. This is less
flexible than the RelaxedEnvironment
approach, but does allow some relaxed binding,
specifically for OS environment variables (so CAPITALS_AND_UNDERSCORES
are synonyms
for period.separated
).
@ConditionalOnExpression
annotations that switch features on and off in
response to SpEL expressions, normally evaluated with place-holders resolved from the
Environment
.
A SpringApplication
has ApplicationListeners
and ApplicationContextInitializers
that
are used to apply customizations to the context or environment. Spring Boot loads a number
of such customizations for use internally from META-INF/spring.factories
. There is more
than one way to register additional ones:
addListeners
and addInitializers
methods on SpringApplication
before you run it.
context.initializer.classes
or
context.listener.classes
.
META-INF/spring.factories
and packaging
a jar file that the applications all use as a library.
The SpringApplication
sends some special ApplicationEvents
to the listeners (even
some before the context is created), and then registers the listeners for events published
by the ApplicationContext
as well. See
Section 20.4, “Application events and listeners” in the
“Spring Boot features” section for a complete list.
You can use the ApplicationBuilder
class to create parent/child ApplicationContext
hierarchies. See Section 20.3, “Fluent builder API”
in the “Spring Boot features” section for more information.
Not all Spring applications have to be web applications (or web services). If you want to
execute some code in a main
method, but also bootstrap a Spring application to set up
the infrastructure to use, then it’s easy with the SpringApplication
features of Spring
Boot. A SpringApplication
changes its ApplicationContext
class depending on whether it
thinks it needs a web application or not. The first thing you can do to help it is to just
leave the servlet API dependencies off the classpath. If you can’t do that (e.g. you are
running 2 applications from the same code base) then you can explicitly call
SpringApplication.setWebEnvironment(false)
, or set the applicationContextClass
property (through the Java API or with external properties).
Application code that you want to run as your business logic can be implemented as a
CommandLineRunner
and dropped into the context as a @Bean
definition.
A SpringApplication
has bean properties (mainly setters) so you can use its Java API as
you create the application to modify its behavior. Or you can externalize the
configuration using properties in spring.main.*
. E.g. in application.properties
you
might have.
spring.main.web_environment=false spring.main.show_banner=false
and then the Spring Boot banner will not be printed on startup, and the application will not be a web application.
Note | |
---|---|
The example above also demonstrates how flexible binding allows the use of
underscores ( |
By default properties from different sources are added to the Spring Environment
in a
defined order (see Chapter 21, Externalized Configuration in
the “Spring Boot features” section for the exact order).
A nice way to augment and modify this is to add @PropertySource
annotations to your
application sources. Classes passed to the SpringApplication
static convenience
methods, and those added using setSources()
are inspected to see if they have
@PropertySources
, and if they do, those properties are added to the Environment
early
enough to be used in all phases of the ApplicationContext
lifecycle. Properties added
in this way have precedence over any added using the default locations, but have lower
priority than system properties, environment variables or the command line.
You can also provide System properties (or environment variables) to change the behavior:
spring.config.name
(SPRING_CONFIG_NAME
), defaults to application
as the root of
the file name.
spring.config.location
(SPRING_CONFIG_LOCATION
) is the file to load (e.g. a classpath
resource or a URL). A separate Environment
property source is set up for this document
and it can be overridden by system properties, environment variables or the
command line.
No matter what you set in the environment, Spring Boot will always load
application.properties
as described above. If YAML is used then files with the “.yml”
extension are also added to the list by default.
See ConfigFileApplicationListener
for more detail.
Some people like to use (for example) --port=9000
instead of --server.port=9000
to
set configuration properties on the command line. You can easily enable this by using
placeholders in application.properties
, e.g.
server.port=${port:8080}
Tip | |
---|---|
If you have enabled maven filtering for the |
Note | |
---|---|
In this specific case the port binding will work in a PaaS environment like Heroku
and Cloud Foundry, since in those two platforms the |
YAML is a superset of JSON and as such is a very convenient syntax for storing external properties in a hierarchical format. E.g.
spring: application: name: cruncher datasource: driverClassName: com.mysql.jdbc.Driver url: jdbc:mysql://localhost/test server: port: 9000
Create a file called application.yml
and stick it in the root of your classpath, and
also add snakeyaml
to your dependencies (Maven coordinates org.yaml:snakeyaml
, already
included if you use the spring-boot-starter
). A YAML file is parsed to a Java
Map<String,Object>
(like a JSON object), and Spring Boot flattens the map so that it
is 1-level deep and has period-separated keys, a lot like people are used to with
Properties
files in Java.
The example YAML above corresponds to an application.properties
file
spring.application.name=cruncher spring.datasource.driverClassName=com.mysql.jdbc.Driver spring.datasource.url=jdbc:mysql://localhost/test server.port=9000
See Section 21.5, “Using YAML instead of Properties” in the “Spring Boot features” section for more information about YAML.
The Spring Environment
has an API for this, but normally you would set a System profile
(spring.profiles.active
) or an OS environment variable (SPRING_PROFILES_ACTIVE
). E.g.
launch your application with a -D
argument (remember to put it before the main class
or jar archive):
$ java -jar -Dspring.profiles.active=production demo-0.0.1-SNAPSHOT.jar
In Spring Boot you can also set the active profile in application.properties
, e.g.
spring.profiles.active=production
A value set this way is replaced by the System property or environment variable setting,
but not by the SpringApplicationBuilder.profiles()
method. Thus the latter Java API can
be used to augment the profiles without changing the defaults.
See Chapter 22, Profiles in the “Spring Boot features” section for more information.
A YAML file is actually a sequence of documents separated by ---
lines, and each
document is parsed separately to a flattened map.
If a YAML document contains a spring.profiles
key, then the profiles value
(comma-separated list of profiles) is fed into the Spring
Environment.acceptsProfiles()
and if any of those profiles is active that document is
included in the final merge (otherwise not).
Example:
server: port: 9000 --- spring: profiles: development server: port: 9001 --- spring: profiles: production server: port: 0
In this example the default port is 9000, but if the Spring profile “development” is active then the port is 9001, and if “production” is active then it is 0.
The YAML documents are merged in the order they are encountered (so later values override earlier ones).
To do the same thing with properties files you can use application-${profile}.properties
to specify profile-specific values.
Spring Boot binds external properties from application.properties
(or .yml
) (and
other places) into an application at runtime. There is not (and technically cannot be)
an exhaustive list of all supported properties in a single location because contributions
can come from additional jar files on your classpath.
A running application with the Actuator features has a configprops
endpoint that shows
all the bound and bindable properties available through @ConfigurationProperties
.
The appendix includes an application.properties
example with a list of the most common properties supported by
Spring Boot. The definitive list comes from searching the source code for
@ConfigurationProperties
and @Value
annotations, as well as the occasional use of
RelaxedEnvironment
.
Servlet
, Filter
, ServletContextListener
and the other listeners supported by the
Servlet spec can be added to your application as @Bean
definitions. Be very careful that
they don’t cause eager initialization of too many other beans because they have to be
installed in the container very early in the application lifecycle (e.g. it’s not a good
idea to have them depend on your DataSource
or JPA configuration). You can work around
restrictions like that by initializing them lazily when first used instead of on
initialization.
In the case of Filters
and Servlets
you can also add mappings and init parameters by
adding a FilterRegistrationBean
or ServletRegistrationBean
instead of or as well as
the underlying component.
In a standalone application the main HTTP port defaults to 8080
, but can be set with
server.port
(e.g. in application.properties
or as a System property). Thanks to
relaxed binding of Environment
values you can also use SERVER_PORT
(e.g. as an OS
environment variable).
To switch off the HTTP endpoints completely, but still create a WebApplicationContext
,
use server.port=-1
(this is sometimes useful for testing).
For more details look at Section 24.2.3, “Customizing embedded servlet containers”
in the “Spring Boot features” section, or the
ServerProperties
source
code.
To scan for a free port (using OS natives to prevent clashes) use server.port=0
.
You can access the port the server is running on from log output or from the
EmbeddedWebApplicationContext
via its EmbeddedServletContainer
. The best way to get
that and be sure that it has initialized is to add a @Bean
of type
ApplicationListener<EmbeddedServletContainerInitializedEvent>
and pull the container
out of the event when it is published.
A really useful thing to do in is to use @IntegrationTest
to set server.port=0
and then inject the actual (“local”) port as a @Value
. For example:
@RunWith(SpringJUnit4ClassRunner.class) @SpringApplicationConfiguration(classes = SampleDataJpaApplication.class) @WebAppConfiguration @IntegrationTest("server.port:0") public class CityRepositoryIntegrationTests { @Autowired EmbeddedWebApplicationContext server; @Value("${local.server.port}") int port; // ... }
Generally you can follow the advice from
Section 54.7, “Discover built-in options for external properties” about
@ConfigurationProperties
(ServerProperties
is the main one here), but also look at
EmbeddedServletContainerCustomizer
and various Tomcat specific *Customizers
that you
can add in one of those. The Tomcat APIs are quite rich so once you have access to the
TomcatEmbeddedServletContainerFactory
you can modify it in a number of ways. Or the
nuclear option is to add your own TomcatEmbeddedServletContainerFactory
.
Use an EmbeddedServletContainerCustomizer
and in that add a TomcatConnectorCustomizer
that sets up the connector to be secure:
@Bean public EmbeddedServletContainerCustomizer containerCustomizer(){ return new MyCustomizer(); } // ... private static class MyCustomizer implements EmbeddedServletContainerCustomizer { @Override public void customize(ConfigurableEmbeddedServletContainer factory) { if(factory instanceof TomcatEmbeddedServletContainerFactory) { customizeTomcat((TomcatEmbeddedServletContainerFactory) factory)); } } public void customizeTomcat(TomcatEmbeddedServletContainerFactory factory) { factory.addConnectorCustomizers(new TomcatConnectorCustomizer() { @Override public void customize(Connector connector) { connector.setPort(serverPort); connector.setSecure(true); connector.setScheme("https"); connector.setAttribute("keyAlias", "tomcat"); connector.setAttribute("keystorePass", "password"); try { connector.setAttribute("keystoreFile", ResourceUtils.getFile("src/ssl/tomcat.keystore").getAbsolutePath()); } catch (FileNotFoundException e) { throw new IllegalStateException("Cannot load keystore", e); } connector.setAttribute("clientAuth", "false"); connector.setAttribute("sslProtocol", "TLS"); connector.setAttribute("SSLEnabled", true); } }); } }
Add a org.apache.catalina.connector.Connector
to the
TomcatEmbeddedServletContainerFactory
which can allow multiple connectors eg a HTTP and
HTTPS connector:
@Bean public EmbeddedServletContainerFactory servletContainer() { TomcatEmbeddedServletContainerFactory tomcat = new TomcatEmbeddedServletContainerFactory(); tomcat.addAdditionalTomcatConnectors(createSslConnector()); return tomcat; } private Connector createSslConnector() { Connector connector = new Connector("org.apache.coyote.http11.Http11NioProtocol"); Http11NioProtocol protocol = (Http11NioProtocol) connector.getProtocolHandler(); try { File keystore = new ClassPathResource("keystore").getFile(); File truststore = new ClassPathResource("keystore").getFile(); connector.setScheme("https"); connector.setSecure(true); connector.setPort(8443); protocol.setSSLEnabled(true); protocol.setKeystoreFile(keystore.getAbsolutePath()); protocol.setKeystorePass("changeit"); protocol.setTruststoreFile(truststore.getAbsolutePath()); protocol.setTruststorePass("changeit"); protocol.setKeyAlias("apitester"); return connector; } catch (IOException ex) { throw new IllegalStateException("can't access keystore: [" + "keystore" + "] or truststore: [" + "keystore" + "]", ex); } }
Spring Boot will automatically configure Tomcat’s RemoteIpValve
if it detects some
environment settings. This allows you to transparently use the standard x-forwarded-for
and x-forwarded-proto
headers that most front-end proxy servers add.
You can switch on the valve by adding some entries to application.properties, e.g.
server.tomcat.remote_ip_header=x-forwarded-for server.tomcat.protocol_header=x-forwarded-proto
Alternatively, you can add the RemoteIpValve
yourself by adding a
TomcatEmbeddedServletContainerFactory
bean.
The Spring Boot starters (spring-boot-starter-web
in particular) use Tomcat as an
embedded container by default. You need to exclude those dependencies and include the
Jetty one instead. Spring Boot provides Tomcat and Jetty dependencies bundled together
as separate starters to help make this process as easy as possible.
Example in Maven:
<dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> <exclusions> <exclusion> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-tomcat</artifactId> </exclusion> </exclusions> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-jetty</artifactId> </dependency>
Example in Gradle:
configurations { compile.exclude module: "spring-boot-starter-tomcat" } dependencies { compile("org.springframework.boot:spring-boot-starter-web:1.0.0.RC3") compile("org.springframework.boot:spring-boot-starter-jetty:1.0.0.RC3") // ... }
Generally you can follow the advice from
Section 54.7, “Discover built-in options for external properties” about
@ConfigurationProperties
(ServerProperties
is the main one here), but also look at
EmbeddedServletContainerCustomizer
. The Jetty APIs are quite rich so once you have
access to the JettyEmbeddedServletContainerFactory
you can modify it in a number
of ways. Or the nuclear option is to add your own JettyEmbeddedServletContainerFactory
.
Tomcat 8 works with Spring Boot, but the default is to use Tomcat 7 (so we can support Java 1.6 out of the box). You should only need to change the classpath to use Tomcat 8 for it to work. For example, using the starter poms in Maven:
<properties> <tomcat.version>8.0.8</tomcat.version> </properties> <dependencies> ... <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> ... </dependencies>
change the classpath to use Tomcat 8 for it to work.
Jetty 9 works with Spring Boot, but the default is to use Jetty 8 (so we can support Java 1.6 out of the box). You should only need to change the classpath to use Jetty 9 for it to work.
If you are using the starter poms and parent you can just add the Jetty starter and change the version properties, e.g. for a simple webapp or service:
<properties> <java.version>1.7</java.version> <jetty.version>9.1.0.v20131115</jetty.version> <servlet-api.version>3.1.0</servlet-api.version> </properties> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> <exclusions> <exclusion> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-tomcat</artifactId> </exclusion> </exclusions> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-jetty</artifactId> </dependency> </dependencies>
Any Spring @RestController
in a Spring Boot application should render JSON response by
default as long as Jackson2 is on the classpath. For example:
@RestController public class MyController { @RequestMapping("/thing") public MyThing thing() { return new MyThing(); } }
As long as MyThing
can be serialized by Jackson2 (e.g. a normal POJO or Groovy object)
then http://localhost:8080/thing
will serve a JSON representation of it by default.
Sometimes in a browser you might see XML responses (but by default only if MyThing
was
a JAXB object) because browsers tend to send accept headers that prefer XML.
Since JAXB is in the JDK the same example as we used for JSON would work, as long as the
MyThing
was annotated as @XmlRootElement
:
@XmlRootElement public class MyThing { private String name; // .. getters and setters }
To get the server to render XML instead of JSON you might have to send an
Accept: text/xml
header (or use a browser).
Spring MVC (client and server side) uses HttpMessageConverters
to negotiate content
conversion in an HTTP exchange. If Jackson is on the classpath you already get a default
converter with a vanilla ObjectMapper
. Spring Boot has some features to make it easier
to customize this behavior.
The smallest change that might work is to just add beans of type
com.fasterxml.jackson.databind.Module
to your context. They will be registered with the
default ObjectMapper
and then injected into the default message converter. To replace
the default ObjectMapper
completely, define a @Bean
of that type and mark it as
@Primary
.
In addition, if your context contains any beans of type ObjectMapper
then all of the
Module
beans will be registered with all of the mappers. So there is a global mechanism
for contributing custom modules when you add new features to your application.
Finally, if you provide any @Beans
of type MappingJackson2HttpMessageConverter
then
they will replace the default value in the MVC configuration. Also, a convenience bean is
provided of type HttpMessageConverters
(always available if you use the default MVC
configuration) which has some useful methods to access the default and user-enhanced
message converters.
See also the Section 56.4, “Customize the @ResponseBody rendering” section and the
WebMvcAutoConfiguration
source code for more details.
Spring uses HttpMessageConverters
to render @ResponseBody
(or responses from
@RestController
). You can contribute additional converters by simply adding beans of
that type in a Spring Boot context. If a bean you add is of a type that would have been
included by default anyway (like MappingJackson2HttpMessageConverter
for JSON
conversions) then it will replace the default value. A convenience bean is provided of
type HttpMessageConverters
(always available if you use the default MVC configuration)
which has some useful methods to access the default and user-enhanced message converters
(useful, for example if you want to manually inject them into a custom RestTemplate
).
As in normal MVC usage, any WebMvcConfigurerAdapter
beans that you provide can also
contribute converters by overriding the configureMessageConverters
method, but unlike
with normal MVC, you can supply only additional converters that you need (because Spring
Boot uses the same mechanism to contribute its defaults). Finally, if you opt-out of the
Spring Boot default MVC configuration by providing your own @EnableWebMvc
configuration,
then you can take control completely and do everything manually using
getMessageConverters
from WebMvcConfigurationSupport
.
See the WebMvcAutoConfiguration
source code for more details.
Spring Boot embraces the Servlet 3 javax.servlet.http.Part
API to support uploading
files. By default Spring Boot configures Spring MVC with a maximum file of 1Mb per
file and a maximum of 10Mb of file data in a single request. You may override these
values, as well as the location to which intermediate data is stored (e.g., to the /tmp
directory) and the threshold past which data is flushed to disk by using the properties
exposed in the MultipartProperties
class. If you want to specify that files be
unlimited, for example, set the multipart.maxFileSize
property to -1
.
The multipart support is helpful when you want to receive multipart encoded file data as
a @RequestParam
-annotated parameter of type MultipartFile
in a Spring MVC controller
handler method.
See the MultipartAutoConfiguration
s
ource for more details.
Spring Boot wants to serve all content from the root of your application /
down. If you
would rather map your own servlet to that URL you can do it, but of course you may lose
some of the other Boot MVC features. To add your own servlet and map it to the root
resource just declare a @Bean
of type Servlet
and give it the special bean name
dispatcherServlet
(You can also create a bean of a different type with that name if
you want to switch it off and not replace it).
The easiest way to take complete control over MVC configuration is to provide your own
@Configuration
with the @EnableWebMvc
annotation. This will leave all MVC
configuration in your hands.
A ViewResolver
is a core component of Spring MVC, translating view names in
@Controller
to actual View
implementations. Note that ViewResolvers
are mainly
used in UI applications, rather than REST-style services (a View
is not used to render
a @ResponseBody
). There are many implementations of ViewResolver
to choose from, and
Spring on its own is not opinionated about which ones you should use. Spring Boot, on the
other hand, installs one or two for you depending on what it finds on the classpath and
in the application context. The DispatcherServlet
uses all the resolvers it finds in
the application context, trying each one in turn until it gets a result, so if you are
adding your own you have to be aware of the order and in which position your resolver is
added.
WebMvcAutoConfiguration
adds the following ViewResolvers
to your context:
InternalResourceViewResolver
with bean id “defaultViewResolver”. This one locates
physical resources that can be rendered using the DefaultServlet
(e.g. static
resources and JSP pages if you are using those). It applies a prefix and a suffix to the
view name and then looks for a physical resource with that path in the servlet context
(defaults are both empty, but accessible for external configuration via
spring.view.prefix
and spring.view.suffix
). It can be overridden by providing a
bean of the same type.
BeanNameViewResolver
with id “beanNameViewResolver”. This is a useful member of the
view resolver chain and will pick up any beans with the same name as the View
being
resolved. It can be overridden by providing a bean of the same type, but it’s unlikely
you will need to do that.
ContentNegotiatingViewResolver
with id “viewResolver” is only added if there are
actually beans of type View
present. This is a “master” resolver, delegating to all
the others and attempting to find a match to the “Accept” HTTP header sent by the
client. There is a useful
blog about ContentNegotiatingViewResolver
that you might like to study to learn more, and also look at the source code for detail.
You can switch off the auto-configured
ContentNegotiatingViewResolver
by defining a bean named “viewResolver”.
ThymeleafViewResolver
with id
“thymeleafViewResolver”. It looks for resources by surrounding the view name with a
prefix and suffix (externalized to spring.thymeleaf.prefix
and
spring.thymeleaf.suffix
, defaults “classpath:/templates/” and “.html”
respectively). It can be overridden by providing a bean of the same name.
FreeMarkerViewResolver
with id
“freeMarkerViewResolver”. It looks for resources in a loader path (externalized to
spring.freemarker.templateLoaderPath
, default “classpath:/templates/”) by
surrounding the view name with a prefix and suffix (externalized to spring.freemarker.prefix
and spring.freemarker.suffix
, with empty and “.ftl” defaults respectively). It can
be overridden by providing a bean of the same name.
Groovy TemplateViewResolver
with id “groovyTemplateViewResolver”. It
looks for resources in a loader path by surrounding the view name with a prefix and
suffix (externalized to spring.groovy.template.prefix
and
spring.groovy.template.suffix
, defaults “classpath:/templates/” and “.tpl”
respectively). It can be overriden by providing a bean of the same name.
VelocityViewResolver
with id “velocityViewResolver”.
It looks for resources in a loader path (externalized to spring.velocity.resourceLoaderPath
,
default “classpath:/templates/”) by surrounding the view name with a prefix and suffix
(externalized to spring.velocity.prefix
and spring.velocity.suffix
, with empty and “.vm”
defaults respectively). It can be overridden by providing a bean of the same name.
Check out WebMvcAutoConfiguration
,
ThymeleafAutoConfiguration
,
FreeMarkerAutoConfiguration
,
GroovyTemplateAutoConfiguration
and
VelocityAutoConfiguration
Spring Boot has no mandatory logging dependence, except for the commons-logging
API, of
which there are many implementations to choose from. To use Logback
you need to include it, and some bindings for commons-logging
on the classpath. The
simplest way to do that is through the starter poms which all depend on
spring-boot-starter-logging
. For a web application you only need
spring-boot-starter-web
since it depends transitively on the logging starter.
For example, using Maven:
<dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency>
Spring Boot has a LoggingSystem
abstraction that attempts to configure logging based on
the content of the classpath. If Logback is available it is the first choice. So if you
put a logback.xml
in the root of your classpath it will be picked up from there. Spring
Boot provides a default base configuration that you can include if you just want to set
levels, e.g.
<?xml version="1.0" encoding="UTF-8"?> <configuration> <include resource="org/springframework/boot/logging/logback/base.xml"/> <logger name="org.springframework.web" level="DEBUG"/> </configuration>
If you look at the default logback.xml
in the spring-boot jar you will see that it uses
some useful System properties which the LoggingSystem
takes care of creating for you.
These are:
${PID}
the current process ID.
${LOG_FILE}
if logging.file
was set in Boot’s external configuration.
${LOG_PATH}
if logging.path
was set (representing a directory for
log files to live in).
Spring Boot also provides some nice ANSI colour terminal output on a console (but not in
a log file) using a custom Logback converter. See the default base.xml
configuration
for details.
If Groovy is on the classpath you should be able to configure Logback with
logback.groovy
as well (it will be given preference if present).
Spring Boot supports Log4j for logging
configuration, but it has to be on the classpath. If you are using the starter poms for
assembling dependencies that means you have to exclude logback and then include log4j
instead. If you aren’t using the starter poms then you need to provide commons-logging
(at least) in addition to Log4j.
The simplest path to using Log4j is probably through the starter poms, even though it requires some jiggling with excludes, e.g. in Maven:
<dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter</artifactId> <exclusions> <exclusion> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-logging</artifactId> </exclusion> </exclusions> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-log4j</artifactId> </dependency>
Note | |
---|---|
The use of the log4j starter gathers together the dependencies for common logging
requirements (e.g. including having Tomcat use |
To override the default settings just define a @Bean
of your own of type DataSource
.
Spring Boot provides a utility builder class DataSourceBuilder
that can be used
to create one of the standard ones (if it is on the classpath), or you can just create
your own, and bind it to a set of Environment
properties e.g.
@Bean @ConfigurationProperties(prefix="datasource.mine") public DataSource dataSource() { return new FancyDataSource(); }
datasource.mine.jdbcUrl=jdbc:h2:mem:mydb datasource.mine.user=sa datasource.mine.poolSize=30
See Section 26.1, “Configure a DataSource” in the
“Spring Boot features” section and the
DataSourceAutoConfiguration
class for more details.
Creating more than one data source works the same as creating the first one. You might
want to mark one of them as @Primary
if you are using the default auto-configuration for
JDBC or JPA (then that one will be picked up by any @Autowired
injections).
@Bean @Primary @ConfigurationProperties(prefix="datasource.primary") public DataSource primaryDataSource() { return DataSourceBuilder.create().build(); } @Bean @ConfigurationProperties(prefix="datasource.secondary") public DataSource secondaryDataSource() { return DataSourceBuilder.create().build(); }
Spring Data can create implementations for you of @Repository
interfaces of various
flavours. Spring Boot will handle all of that for you as long as those @Repositories
are included in the same package (or a sub-package) of your @EnableAutoConfiguration
class.
For many applications all you will need is to put the right Spring Data dependencies on
your classpath (there is a spring-boot-starter-data-jpa
for JPA and a
spring-boot-starter-data-mongodb
for Mongodb), create some repository interfaces to handle your
@Entity
objects. Examples are in the JPA sample
or the Mongodb sample.
Spring Boot tries to guess the location of your @Repository
definitions, based on the
@EnableAutoConfiguration
it finds. To get more control, use the @EnableJpaRepositories
annotation (from Spring Data JPA).
Spring Boot tries to guess the location of your @Entity
definitions, based on the
@EnableAutoConfiguration
it finds. To get more control, you can use the @EntityScan
annotation, e.g.
@Configuration @EnableAutoConfiguration @EntityScan(basePackageClasses=City.class) public class Application { //... }
Spring Data JPA already provides some vendor-independent configuration options (e.g. for SQL logging) and Spring Boot exposes those, and a few more for hibernate as external configuration properties. The most common options to set are:
spring.jpa.hibernate.ddl-auto: create-drop spring.jpa.hibernate.naming_strategy: org.hibernate.cfg.ImprovedNamingStrategy spring.jpa.database: H2 spring.jpa.show-sql: true
(Because of relaxed data binding hyphens or underscores should work equally well as
property keys.) The ddl-auto
setting is a special case in that it has different
defaults depending on whether you are using an embedded database (create-drop
) or not
(none
). In addition all properties in spring.jpa.properties.*
are passed through as
normal JPA properties (with the prefix stripped) when the local EntityManagerFactory
is
created.
See HibernateJpaAutoConfiguration
and JpaBaseConfiguration
for more details.
To take full control of the configuration of the EntityManagerFactory
, you need to add
a @Bean
named "entityManagerFactory". Spring Boot auto-configuration switches off its
entity manager based on the presence of a bean of that type.
Even if the default EntityManagerFactory
works fine, you will need to define a new one
because otherwise the presence of the second bean of that type will switch off the
default. To make it easy to do that you can use the convenient EntityManagerBuilder
provided by Spring Boot, or if you prefer you can just use the
LocalContainerEntityManagerFactoryBean
directly from Spring ORM.
Example:
// add two data sources configured as above @Bean public LocalContainerEntityManagerFactoryBean customerEntityManagerFactory( EntityManagerFactoryBuilder builder) { return builder .dataSource(customerDataSource()) .packages(Customer.class) .persistenceUnit("customers") .build(); } @Bean public LocalContainerEntityManagerFactoryBean orderEntityManagerFactory( EntityManagerFactoryBuilder builder) { return builder .dataSource(orderDataSource()) .packages(Order.class) .persistenceUnit("orders") .build(); }
The configuration above almost works on its own. To complete the picture you need to
configure TransactionManagers
for the two EntityManagers
as well. One of them could
be picked up by the default JpaTransactionManager
in Spring Boot if you mark it as
@Primary
. The other would have to be explicitly injected into a new instance. Or you
might be able to use a JTA transaction manager spanning both.
Spring doesn’t require the use of XML to configure the JPA provider, and Spring Boot
assumes you want to take advantage of that feature. If you prefer to use persistence.xml
then you need to define your own @Bean
of type LocalEntityManagerFactoryBean
(with
id "entityManagerFactory", and set the persistence unit name there.
See
JpaBaseConfiguration
for the default settings.
An SQL database can be initialized in different ways depending on what your stack is. Or of course you can do it manually as long as the database is a separate process.
JPA has features for DDL generation, and these can be set up to run on startup against the database. This is controlled through two external properties:
spring.jpa.generate-ddl
(boolean) switches the feature on and off and is vendor
independent.
spring.jpa.hibernate.ddl-auto
(enum) is a Hibernate feature that controls the
behavior in a more fine-grained way. See below for more detail.
You can set spring.jpa.hibernate.ddl-auto
explicitly and the standard Hibernate property
values are none
, validate
, update
, create-drop
. Spring Boot chooses a default
value for you based on whether it thinks your database is embedded (default create-drop
)
or not (default none
). An embedded database is detected by looking at the Connection
type: hsqldb
, h2
and derby
are embedded, the rest are not. Be careful when switching
from in-memory to a “real” database that you don’t make assumptions about the existence of
the tables and data in the new platform. You either have to set ddl-auto
explicitly, or
use one of the other mechanisms to initialize the database.
In addition, a file named import.sql
in the root of the classpath will be executed on
startup. This can be useful for demos and for testing if you are careful, but probably
not something you want to be on the classpath in production. It is a Hibernate feature
(nothing to do with Spring).
Spring JDBC has a DataSource
initializer feature. Spring Boot enables it by default and
loads SQL from the standard locations schema.sql
and data.sql
(in the root of the
classpath). In addition Spring Boot will load the schema-${platform}.sql
and data-${platform}.sql
files (if present), where
platform
is the value of spring.datasource.platform
, e.g. you might choose to set
it to the vendor name of the database (hsqldb
, h2
, oracle
, mysql
,
postgresql
etc.). Spring Boot enables the failfast feature of the Spring JDBC
initializer by default, so if the scripts cause exceptions the application will fail
to start.
To disable the failfast you can set spring.datasource.continueOnError=true
. This can be
useful once an application has matured and been deployed a few times, since the scripts
can act as “poor man’s migrations” — inserts that fail mean that the data is already
there, so there would be no need to prevent the application from running, for instance.
If you are using Spring Batch then it comes pre-packaged with SQL initialization scripts
for most popular database platforms. Spring Boot will detect your database type, and
execute those scripts by default, and in this case will switch the fail fast setting to
false (errors are logged but do not prevent the application from starting). This is
because the scripts are known to be reliable and generally do not contain bugs, so errors
are ignorable, and ignoring them makes the scripts idempotent. You can switch off the
initialization explicitly using spring.batch.initializer.enabled=false
.
Spring Boot works fine with higher level migration tools Flyway (SQL-based) and Liquibase (XML). In general we prefer Flyway because it is easier on the eyes, and it isn’t very common to need platform independence: usually only one or at most couple of platforms is needed.
To automatically run Flyway database migrations on startup, add the
org.flywaydb:flyway-core
to your classpath.
The migrations are scripts in the form V<VERSION>__<NAME>.sql
(with
<VERSION>
an underscore-separated version, e.g. "1" or "2_1"). By
default they live in a folder classpath:db/migration
but you can
modify that using flyway.locations
(a list). See the Flyway class from
flyway-core for details of available settings like schemas etc. In
addition Spring Boot provides a small set of properties in
FlywayProperties
that can be used to disable the migrations, or switch off the location checking.
By default Flyway will autowire the (@Primary
) DataSource
in your context and
use that for migrations. If you like to use a different DataSource
you can create
one and mark its @Bean
as @FlywayDataSource
- if you do that remember to create
another one and mark it as @Primary
if you want 2 data sources.
Or you can use Flyway’s native DataSource
by setting flyway.[url,user,password]
in external properties.
There is a Flyway sample so you can see how to set things up.
To automatically run Liquibase database migrations on startup, add the
org.liquibase:liquibase-core
to your classpath.
The master change log is by default read from db/changelog/db.changelog-master.yaml
but
can be set using liquibase.change-log
. See
LiquibaseProperties
for details of available settings like contexts, default schema etc.
There is a Liquibase sample so you can see how to set things up.
Spring Batch auto configuration is enabled by adding @EnableBatchProcessing
(from Spring Batch) somewhere in your context.
By default it executes all Jobs
in the application context on startup (see
JobLauncherCommandLineRunner
for details). You can narrow down to a specific job or jobs by specifying
spring.batch.job.names
(comma separated job name patterns).
If the application context includes a JobRegistry
then the jobs in
spring.batch.job.names
are looked up in the registry instead of being autowired from the
context. This is a common pattern with more complex systems where multiple jobs are
defined in child contexts and registered centrally.
See BatchAutoConfiguration and @EnableBatchProcessing for more details.
In a standalone application the Actuator HTTP port defaults to the same as the main HTTP
port. To make the application listen on a different port set the external property
management.port
. To listen on a completely different network address (e.g. if you have
an internal network for management and an external one for user applications) you can
also set management.address
to a valid IP address that the server is able to bind to.
For more detail look at the
ManagementServerProperties
source code and
Section 33.3, “Customizing the management server port”
in the “Production-ready features” section.
The Actuator installs a “whitelabel” error page that you will see in browser client if
you encounter a server error (machine clients consuming JSON and other media types should
see a sensible response with the right error code). To switch it off you can set
error.whitelabel.enabled=false
, but normally in addition or alternatively to that you
will want to add your own error page replacing the whitelabel one. Exactly how you do this
depends on the templating technology that you are using. For example, if you are using
Thymeleaf you would add an error.html
template and if you are using FreeMarker you would
add an error.ftl
template. In general what you need is a View
that resolves with a name
of error
, and/or a @Controller
that handles the /error
path. Unless you replaced some
of the default configuration you should find a BeanNameViewResolver
in your
ApplicationContext
so a @Bean
with id error
would be a simple way of doing that.
Look at ErrorMvcAutoConfiguration
for more options.
If you define a @Configuration
with @EnableWebSecurity
anywhere in your application
it will switch off the default webapp security settings in Spring Boot. To tweak the
defaults try setting properties in security.*
(see
SecurityProperties
for details of available settings) and SECURITY
section of
Common application properties.
If you provide a @Bean
of type AuthenticationManager
the default one will not be
created, so you have the full feature set of Spring Security available (e.g.
various authentication options).
Spring Security also provides a convenient AuthenticationManagerBuilder
which can be
used to build an AuthenticationManager
with common options. The recommended way to
use this in a webapp is to inject it into a void method in a
WebSecurityConfigurerAdapter
, e.g.
@Configuration public class SecurityConfiguration extends WebSecurityConfigurerAdapter { @Autowired public void configureGlobal(AuthenticationManagerBuilder auth) throws Exception { auth.inMemoryAuthentication() .withUser("barry").password("password").roles("USER"); // ... etc. } // ... other stuff for application security }
You will get the best results if you put this in a nested class, or a standalone class
(i.e. not mixed in with a lot of other @Beans
that might be allowed to influence the
order of instantiation). The secure web sample
is a useful template to follow.
Ensuring that all your main endpoints are only available over HTTPS is an important
chore for any application. If you are using Tomcat as a servlet container, then
Spring Boot will add Tomcat’s own RemoteIpValve
automatically if it detects some
environment settings, and you should be able to rely on the HttpServletRequest
to
report whether it is secure or not (even downstream of a proxy server that handles the
real SSL termination). The standard behavior is determined by the presence or absence of
certain request headers (x-forwarded-for
and x-forwarded-proto
), whose names are
conventional, so it should work with most front end proxies. You can switch on the valve
by adding some entries to application.properties
, e.g.
server.tomcat.remote_ip_header=x-forwarded-for server.tomcat.protocol_header=x-forwarded-proto
(The presence of either of those properties will switch on the valve. Or you can add the
RemoteIpValve
yourself by adding a TomcatEmbeddedServletContainerFactory
bean.)
Spring Security can also be configured to require a secure channel for all (or some
requests). To switch that on in a Spring Boot application you just need to set
security.require_https
to true
in application.properties
.
There are several options for hot reloading. Running in an IDE (especially with debugging on) is a good way to do development (all modern IDEs allow reloading of static resources and usually also hot-swapping of Java class changes). The Maven and Gradle plugins also support running from the command line with reloading of static files. You can use that with an external css/js compiler process if you are writing that code with higher level tools.
If you are using Thymeleaf, then set spring.thymeleaf.cache
to false
. See
ThymeleafAutoConfiguration
for other Thymeleaf customization options.
If you are using FreeMarker, then set spring.freemarker.cache
to false
. See
FreeMarkerAutoConfiguration
for other FreeMarker customization options.
If you are using Groovy templates, then set spring.groovy.template.cache
to false
. See
GroovyTemplateAutoConfiguration
for other Groovy customization options.
If you are using Velocity, then set spring.velocity.cache
to false
. See
VelocityAutoConfiguration
for other Velocity customization options.
Modern IDEs (Eclipse, IDEA, etc.) all support hot swapping of bytecode, so if you make a change that doesn’t affect class or method signatures it should reload cleanly with no side effects.
Spring Loaded goes a little further in
that it can reload class definitions with changes in the method signatures. With some
customization it can force an ApplicationContext
to refresh itself (but there is no
general mechanism to ensure that would be safe for a running application anyway, so it
would only ever be a development time trick probably).
If you use a Maven build that inherits from spring-boot-starter-parent
but you want
to override a specific third-party dependency you can add appropriate <properties>
elements. Browse the spring-dependencies
POM for a complete list of properties. For example, to pick a different slf4j
version
you would add the following:
<properties> <slf4j.version>1.7.5<slf4j.version> </properties>
Warning | |
---|---|
Each Spring Boot release is designed and tested against a specific set of third-party dependencies. Overriding versions may cause compatibility issues. |
The spring-boot-maven-plugin
can be used to create an executable “fat” JAR. If you
are using the spring-boot-starter-parent
POM you can simply declare the plugin and
your jars will be repackaged:
<build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> </plugins> </build>
If you are not using the parent POM you can still use the plugin, however, you must
additionally add an <executions>
section:
<build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> <version>1.1.0.RC1</version> <executions> <execution> <goals> <goal>repackage</goal> </goals> </execution> </executions> </plugin> </plugins> </build>
See the plugin documentation for full usage details.
To attach a remote debugger to a Spring Boot application started with Maven you can use
the mvnDebug
command rather than mvn
. For example:
$ mvnDebug spring-boot:run
You can now attach a remote debugger to your running application on port 8000
.
To build with Ant you need to grab dependencies, compile and then create a jar or war archive as normal. To make it executable:
Main-Class
, e.g. JarLauncher
for a jar file, and
specify the other properties it needs as manifest entries, principally a Start-Class
.
provided
(embedded container) dependencies in a nested lib-provided
directory.
Remember not to compress the entries in the archive.
spring-boot-loader
classes at the root of the archive (so the Main-Class
is available).
Example:
<target name="build" depends="compile"> <copy todir="target/classes/lib"> <fileset dir="lib/runtime" /> </copy> <jar destfile="target/spring-boot-sample-actuator-${spring-boot.version}.jar" compress="false"> <fileset dir="target/classes" /> <fileset dir="src/main/resources" /> <zipfileset src="lib/loader/spring-boot-loader-jar-${spring-boot.version}.jar" /> <manifest> <attribute name="Main-Class" value="org.springframework.boot.loader.JarLauncher" /> <attribute name="Start-Class" value="${start-class}" /> </manifest> </jar> </target>
The Actuator Sample has a build.xml
that should work if you run it with
$ ant -lib <path_to>/ivy-2.2.jar
after which you can run the application with
$ java -jar target/*.jar
Use the SpringBootServletInitializer
base class, which is picked up by Spring’s
Servlet 3.0 support on deployment. Add an extension of that to your project and build a
war file as normal. For more detail, see the
“Converting a jar Project to a war” guide
on the spring.io website and the sample below.
The war file can also be executable if you use the Spring Boot build tools. In that case
the embedded container classes (to launch Tomcat for instance) have to be added to the
war in a lib-provided
directory. The tools will take care of that as long as the
dependencies are marked as "provided" in Maven or Gradle. Here’s a Maven example
in the Boot Samples.
Older Servlet containers don’t have support for the ServletContextInitializer
bootstrap
process used in Servlet 3.0. You can still use Spring and Spring Boot in these containers
but you are going to need to add a web.xml
to your application and configure it to load
an ApplicationContext
via a DispatcherServlet
.
For a non-web application it should be easy (throw away the code that creates your
ApplicationContext
and replace it with calls to SpringApplication
or
SpringApplicationBuilder
). Spring MVC web applications are generally amenable to first
creating a deployable war application, and then migrating it later to an executable war
and/or jar. Useful reading is in the Getting
Started Guide on Converting a jar to a war.
Create a deployable war by extending SpringBootServletInitializer
(e.g. in a class
called Application
), and add the Spring Boot @EnableAutoConfiguration
annotation.
Example:
@Configuration @EnableAutoConfiguration @ComponentScan public class Application extends SpringBootServletInitializer { @Override protected SpringApplicationBuilder configure(SpringApplicationBuilder application) { return application.sources(Application.class); } }
Remember that whatever you put in the sources
is just a Spring ApplicationContext
and
normally anything that already works should work here. There might be some beans you can
remove later and let Spring Boot provide its own defaults for them, but it should be
possible to get something working first.
Static resources can be moved to /public
(or /static
or /resources
or
/META-INF/resources
) in the classpath root. Same for messages.properties
(Spring Boot
detects this automatically in the root of the classpath).
Vanilla usage of Spring DispatcherServlet
and Spring Security should require no further
changes. If you have other features in your application, using other servlets or filters
for instance, then you may need to add some configuration to your Application
context,
replacing those elements from the web.xml
as follows:
@Bean
of type Servlet
or ServletRegistrationBean
installs that bean in the
container as if it was a <servlet/>
and <servlet-mapping/>
in web.xml
.
@Bean
of type Filter
or FilterRegistrationBean
behaves similarly (like a
<filter/>
and <filter-mapping/>
.
ApplicationContext
in an XML file can be added to an @Import
in your
Application
. Or simple cases where annotation configuration is heavily used already
can be recreated in a few lines as @Bean
definitions.
Once the war is working we make it executable by adding a main
method to our
Application
, e.g.
public static void main(String[] args) { SpringApplication.run(Application.class, args); }
Applications can fall into more than one category:
web.xml
.
web.xml
.
All of these should be amenable to translation, but each might require slightly different tricks.
Servlet 3.0 applications might translate pretty easily if they already use the Spring
Servlet 3.0 initializer support classes. Normally all the code from an existing
WebApplicationInitializer
can be moved into a SpringBootServletInitializer
. If your
existing application has more than one ApplicationContext
(e.g. if it uses
AbstractDispatcherServletInitializer
) then you might be able to squash all your context
sources into a single SpringApplication
. The main complication you might encounter is if
that doesn’t work and you need to maintain the context hierarchy. See the
entry on building a hierarchy for
examples. An existing parent context that contains web-specific features will usually
need to be broken up so that all the ServletContextAware
components are in the child
context.
Applications that are not already Spring applications might be convertible to a Spring Boot application, and the guidance above might help, but your mileage may vary.
Various properties can be specified inside your application.properties
/application.yml
file or as command line switches. This section provides a list common Spring Boot
properties and references to the underlying classes that consume them.
Note | |
---|---|
Property contributions can come from additional jar files on your classpath so you should not consider this an exhaustive list. It is also perfectly legit to define your own properties. |
Warning | |
---|---|
This sample file is meant as a guide only. Do not copy/paste the entire content into your application; rather pick only the properties that you need. |
# =================================================================== # COMMON SPRING BOOT PROPERTIES # # This sample file is provided as a guideline. Do NOT copy it in its # entirety to your own application. ^^^ # =================================================================== # ---------------------------------------- # CORE PROPERTIES # ---------------------------------------- # SPRING CONFIG (ConfigFileApplicationListener) spring.config.name= # config file name (default to 'application') spring.config.location= # location of config file # PROFILES spring.profiles= # comma list of active profiles # APPLICATION SETTINGS (SpringApplication) spring.main.sources= spring.main.web-environment= # detect by default spring.main.show-banner=true spring.main....= # see class for all properties # LOGGING logging.path=/var/logs logging.file=myapp.log logging.config= # IDENTITY (ContextIdApplicationContextInitializer) spring.application.name= spring.application.index= # EMBEDDED SERVER CONFIGURATION (ServerProperties) server.port=8080 server.address= # bind to a specific NIC server.session-timeout= # session timeout in seconds server.context-path= # the context path, defaults to '/' server.servlet-path= # the servlet path, defaults to '/' server.tomcat.access-log-pattern= # log pattern of the access log server.tomcat.access-log-enabled=false # is access logging enabled server.tomcat.protocol-header=x-forwarded-proto # ssl forward headers server.tomcat.remote-ip-header=x-forwarded-for server.tomcat.basedir=/tmp # base dir (usually not needed, defaults to tmp) server.tomcat.background-processor-delay=30; # in seconds server.tomcat.max-threads = 0 # number of threads in protocol handler server.tomcat.uri-encoding = UTF-8 # character encoding to use for URL decoding # SPRING MVC (HttpMapperProperties) http.mappers.json-pretty-print=false # pretty print JSON http.mappers.json-sort-keys=false # sort keys spring.mvc.locale= # set fixed locale, e.g. en_UK spring.mvc.date-format= # set fixed date format, e.g. dd/MM/yyyy spring.mvc.message-codes-resolver-format= # PREFIX_ERROR_CODE / POSTFIX_ERROR_CODE spring.view.prefix= # MVC view prefix spring.view.suffix= # ... and suffix spring.resources.cache-period= # cache timeouts in headers sent to browser spring.resources.add-mappings=true # if default mappings should be added # THYMELEAF (ThymeleafAutoConfiguration) spring.thymeleaf.prefix=classpath:/templates/ spring.thymeleaf.suffix=.html spring.thymeleaf.mode=HTML5 spring.thymeleaf.encoding=UTF-8 spring.thymeleaf.content-type=text/html # ;charset=<encoding> is added spring.thymeleaf.cache=true # set to false for hot refresh # FREEMARKER (FreeMarkerAutoConfiguration) spring.freemarker.allowRequestOverride=false spring.freemarker.allowSessionOverride=false spring.freemarker.cache=true spring.freemarker.checkTemplateLocation=true spring.freemarker.contentType=text/html spring.freemarker.exposeRequestAttributes=false spring.freemarker.exposeSessionAttributes=false spring.freemarker.exposeSpringMacroHelpers=false spring.freemarker.prefix= spring.freemarker.requestContextAttribute= spring.freemarker.settings.*= spring.freemarker.suffix=.ftl spring.freemarker.templateEncoding=UTF-8 spring.freemarker.templateLoaderPath=classpath:/templates/ spring.freemarker.viewNames= # whitelist of view names that can be resolved # GROOVY TEMPLATES (GroovyTemplateAutoConfiguration) spring.groovy.template.allowRequestOverride=false spring.groovy.template.allowSessionOverride=false spring.groovy.template.cache=true spring.groovy.template.configuration.*= # See Groovy's TemplateConfiguration spring.groovy.template.contentType=text/html spring.groovy.template.prefix=classpath:/templates/ spring.groovy.template.suffix=.tpl spring.groovy.template.templateEncoding=UTF-8 spring.groovy.template.viewNames= # whitelist of view names that can be resolved # VELOCITY TEMPLATES (VelocityAutoConfiguration) spring.velocity.allowRequestOverride=false spring.velocity.allowSessionOverride=false spring.velocity.cache=true spring.velocity.checkTemplateLocation=true spring.velocity.contentType=text/html spring.velocity.dateToolAttribute= spring.velocity.exposeRequestAttributes=false spring.velocity.exposeSessionAttributes=false spring.velocity.exposeSpringMacroHelpers=false spring.velocity.numberToolAttribute= spring.velocity.prefix= spring.velocity.properties.*= spring.velocity.requestContextAttribute= spring.velocity.resourceLoaderPath=classpath:/templates/ spring.velocity.suffix=.vm spring.velocity.templateEncoding=UTF-8 spring.velocity.viewNames= # whitelist of view names that can be resolved # INTERNATIONALIZATION (MessageSourceAutoConfiguration) spring.messages.basename=messages spring.messages.cacheSeconds=-1 spring.messages.encoding=UTF-8 # SECURITY (SecurityProperties) security.user.name=user # login username security.user.password= # login password security.user.role=USER # role assigned to the user security.require-ssl=false # advanced settings ... security.enable-csrf=false security.basic.enabled=true security.basic.realm=Spring security.basic.path= # /** security.headers.xss=false security.headers.cache=false security.headers.frame=false security.headers.contentType=false security.headers.hsts=all # none / domain / all security.sessions=stateless # always / never / if_required / stateless security.ignored=false # DATASOURCE (DataSourceAutoConfiguration & AbstractDataSourceConfiguration) spring.datasource.name= # name of the data source spring.datasource.initialize=true # populate using data.sql spring.datasource.schema= # a schema resource reference spring.datasource.platform= # the platform to use in the schema resource (schema-${platform}.sql) spring.datasource.continueOnError=false # continue even if can't be initialized spring.datasource.separator=; # statement separator in SQL initialization scripts spring.datasource.driverClassName= # JDBC Settings... spring.datasource.url= spring.datasource.username= spring.datasource.password= spring.datasource.max-active=100 # Advanced configuration... spring.datasource.max-idle=8 spring.datasource.min-idle=8 spring.datasource.initial-size=10 spring.datasource.validation-query= spring.datasource.test-on-borrow=false spring.datasource.test-on-return=false spring.datasource.test-while-idle= spring.datasource.time-between-eviction-runs-millis= spring.datasource.min-evictable-idle-time-millis= spring.datasource.max-wait-millis= # MONGODB (MongoProperties) spring.data.mongodb.host= # the db host spring.data.mongodb.port=27017 # the connection port (defaults to 27107) spring.data.mongodb.uri=mongodb://localhost/test # connection URL # JPA (JpaBaseConfiguration, HibernateJpaAutoConfiguration) spring.jpa.properties.*= # properties to set on the JPA connection spring.jpa.openInView=true spring.jpa.show-sql=true spring.jpa.database-platform= spring.jpa.database= spring.jpa.generate-ddl=false # ignored by Hibernate, might be useful for other vendors spring.jpa.hibernate.naming-strategy= # naming classname spring.jpa.hibernate.defer-ddl=true # defer processing of DDL until application is running spring.jpa.hibernate.ddl-auto= # defaults to create-drop for embedded dbs # SOLR (SolrProperties}) spring.data.solr.host=http://127.0.0.1:8983/solr spring.data.solr.zkHost= # ELASTICSEARCH (ElasticsearchProperties}) spring.data.elasticsearch.cluster-name= # The cluster name (defaults to elasticsearch) spring.data.elasticsearch.cluster-node= # The address of the server node (if not specified starts a client node) spring.data.elasticsearch.local=true # if local mode should be used with client nodes # FLYWAY (FlywayProperties) flyway.locations=classpath:db/migrations # locations of migrations scripts flyway.schemas= # schemas to update flyway.initVersion= 1 # version to start migration flyway.prefix=V flyway.suffix=.sql flyway.enabled=true flyway.url= # JDBC url if you want Flyway to create its own DataSource flyway.user= # JDBC username if you want Flyway to create its own DataSource flyway.password= # JDBC password if you want Flyway to create its own DataSource # LIQUIBASE (LiquibaseProperties) liquibase.change-log=classpath:/db/changelog/db.changelog-master.yaml liquibase.contexts= # runtime contexts to use liquibase.default-schema= # default database schema to use liquibase.drop-first=false liquibase.enabled=true # JMX spring.jmx.enabled=true # Expose MBeans from Spring # RABBIT (RabbitProperties) spring.rabbitmq.host= # connection host spring.rabbitmq.port= # connection port spring.rabbitmq.addresses= # connection addresses (e.g. myhost:9999,otherhost:1111) spring.rabbitmq.username= # login user spring.rabbitmq.password= # login password spring.rabbitmq.virtualhost= spring.rabbitmq.dynamic= # REDIS (RedisProperties) spring.redis.host=localhost # server host spring.redis.password= # server password spring.redis.port=6379 # connection port spring.redis.pool.max-idle=8 # pool settings ... spring.redis.pool.min-idle=0 spring.redis.pool.max-active=8 spring.redis.pool.max-wait=-1 # ACTIVEMQ (ActiveMQProperties) spring.activemq.broker-url=tcp://localhost:61616 # connection URL spring.activemq.user= spring.activemq.password= spring.activemq.in-memory=true # broker kind to create if no broker-url is specified spring.activemq.pooled=false # HornetQ (HornetQProperties) spring.hornetq.mode= # connection mode (native, embedded) spring.hornetq.host=localhost # hornetQ host (native mode) spring.hornetq.port=5445 # hornetQ port (native mode) spring.hornetq.embedded.enabled=true # if the embedded server is enabled (needs hornetq-jms-server.jar) spring.hornetq.embedded.persistent=false # message persistence spring.hornetq.embedded.data-directory= # location of data content (when persistence is enabled) spring.hornetq.embedded.queues= # comma separate queues to create on startup spring.hornetq.embedded.topics= # comma separate topics to create on startup spring.hornetq.embedded.cluster-password = # customer password (randomly generated by default) # JMS (JmsTemplateProperties) spring.jms.pub-sub-domain= # false for queue (default), true for topic # SPRING BATCH (BatchDatabaseInitializer) spring.batch.job.names=job1,job2 spring.batch.job.enabled=true spring.batch.initializer.enabled=true spring.batch.schema= # batch schema to load # AOP spring.aop.auto= spring.aop.proxyTargetClass= # FILE ENCODING (FileEncodingApplicationListener) spring.mandatory-file-encoding=false # SPRING SOCIAL (SocialWebAutoConfiguration) spring.social.auto_connection_views=true # Set to true for default connection views or false if you provide your own # SPRING SOCIAL FACEBOOK (FacebookAutoConfiguration) spring.social.facebook.appId= # your application's Facebook App ID spring.social.facebook.appSecret= # your application's Facebook App Secret # SPRING SOCIAL LINKEDIN (LinkedInAutoConfiguration) spring.social.linkedin.appId= # your application's LinkedIn App ID spring.social.linkedin.appSecret= # your application's LinkedIn App Secret # SPRING SOCIAL TWITTER (TwitterAutoConfiguration) spring.social.twitter.appId= # your application's Twitter App ID spring.social.twitter.appSecret= # your application's Twitter App Secret # ---------------------------------------- # ACTUATOR PROPERTIES # ---------------------------------------- # MANAGEMENT HTTP SERVER (ManagementServerProperties) management.port= # defaults to 'server.port' management.address= # bind to a specific NIC management.contextPath= # default to '/' # ENDPOINTS (AbstractEndpoint subclasses) endpoints.autoconfig.id=autoconfig endpoints.autoconfig.sensitive=true endpoints.autoconfig.enabled=true endpoints.beans.id=beans endpoints.beans.sensitive=true endpoints.beans.enabled=true endpoints.configprops.id=configprops endpoints.configprops.sensitive=true endpoints.configprops.enabled=true endpoints.configprops.keys-to-sanitize=password,secret endpoints.dump.id=dump endpoints.dump.sensitive=true endpoints.dump.enabled=true endpoints.env.id=env endpoints.env.sensitive=true endpoints.env.enabled=true endpoints.health.id=health endpoints.health.sensitive=false endpoints.health.enabled=true endpoints.info.id=info endpoints.info.sensitive=false endpoints.info.enabled=true endpoints.metrics.id=metrics endpoints.metrics.sensitive=true endpoints.metrics.enabled=true endpoints.shutdown.id=shutdown endpoints.shutdown.sensitive=true endpoints.shutdown.enabled=false endpoints.trace.id=trace endpoints.trace.sensitive=true endpoints.trace.enabled=true # MVC ONLY ENDPOINTS endpoints.jolokia.path=jolokia endpoints.jolokia.sensitive=true endpoints.jolokia.enabled=true # when using Jolokia endpoints.error.path=/error # JMX ENDPOINT (EndpointMBeanExportProperties) endpoints.jmx.enabled=true endpoints.jmx.domain= # the JMX domain, defaults to 'org.springboot' endpoints.jmx.unique-names=false endpoints.jmx.enabled=true endpoints.jmx.staticNames= # JOLOKIA (JolokiaProperties) jolokia.config.*= # See Jolokia manual # REMOTE SHELL shell.auth=simple # jaas, key, simple, spring shell.command-refresh-interval=-1 shell.command-path-pattern= # classpath*:/commands/**, classpath*:/crash/commands/** shell.config-path-patterns= # classpath*:/crash/* shell.disabled-plugins=false # don't expose plugins shell.ssh.enabled= # ssh settings ... shell.ssh.keyPath= shell.ssh.port= shell.telnet.enabled= # telnet settings ... shell.telnet.port= shell.auth.jaas.domain= # authentication settings ... shell.auth.key.path= shell.auth.simple.user.name= shell.auth.simple.user.password= shell.auth.spring.roles= # GIT INFO spring.git.properties= # resource ref to generated git info properties file
Here is a list of all auto configuration classes provided by Spring Boot with links to
documentation and source code. Remember to also look at the autoconfig report in your
application for more details of which features are switched on.
(start the app with --debug
or -Ddebug
, or in an Actuator application use the
autoconfig
endpoint).
The following auto-configuration classes are from the spring-boot-autoconfigure
module:
Configuration Class | Links |
---|---|
The following auto-configuration classes are from the spring-boot-actuator
module:
Configuration Class | Links |
---|---|
The spring-boot-loader
modules allows Spring Boot to support executable jar and
war files. If you’re using the Maven or Gradle plugin, executable jars are
automatically generated and you generally won’t need to know the details of how
they work.
If you need to create executable jars from a different build system, or if you are just curious about the underlying technology, this section provides some background.
Java does not provide any standard way to load nested jar files (i.e. jar files that are themselves contained within a jar). This can be problematic if you are looking to distribute a self contained application that you can just run from the command line without unpacking.
To solve this problem, many developers use “shaded” jars. A shaded jar simply packages all classes, from all jars, into a single uber jar. The problem with shaded jars is that it becomes hard to see which libraries you are actually using in your application. It can also be problematic if the the same filename is used (but with different content) in multiple jars. Spring Boot takes a different approach and allows you to actually nest jars directly.
Spring Boot Loader compatible jar files should be structured in the following way:
example.jar | +-META-INF | +-MANIFEST.MF +-org | +-springframework | +-boot | +-loader | +-<spring boot loader classes> +-com | +-mycompany | + project | +-YouClasses.class +-lib +-dependency1.jar +-dependency2.jar
Dependencies should be placed in a nested lib
directory.
Spring Boot Loader compatible war files should be structured in the following way:
example.jar | +-META-INF | +-MANIFEST.MF +-org | +-springframework | +-boot | +-loader | +-<spring boot loader classes> +-WEB-INF +-classes | +-com | +-mycompany | +-project | +-YouClasses.class +-lib | +-dependency1.jar | +-dependency2.jar +-lib-provided +-servlet-api.jar +-dependency3.jar
Dependencies should be placed in a nested WEB-INF/lib
directory. Any dependencies
that are required when running embedded but are not required when deploying to
a traditional web container should be placed in WEB-INF/lib-provided
.
The core class used to support loading nested jars is
org.springframework.boot.loader.jar.JarFile
. It allows you load jar
content from a standard jar file, or from nested child jar data. When first loaded, the
location of each JarEntry
is mapped to a physical file offset of the outer jar:
myapp.jar +---------+---------------------+ | | /lib/mylib.jar | | A.class |+---------+---------+| | || B.class | B.class || | |+---------+---------+| +---------+---------------------+ ^ ^ ^ 0063 3452 3980
The example above shows how A.class
can be found in myapp.jar
position 0063
.
B.class
from the nested jar can actually be found in myapp.jar
position 3452
and B.class
is at position 3980
.
Armed with this information, we can load specific nested entries by simply seeking to appropriate part if the outer jar. We don’t need to unpack the archive and we don’t need to read all entry data into memory.
Spring Boot Loader strives to remain compatible with existing code and libraries.
org.springframework.boot.loader.jar.JarFile
extends from java.util.jar.JarFile
and
should work as a drop-in replacement. The RandomAccessJarFile.getURL()
method will
return a URL
that opens a java.net.JarURLConnection
compatible connection.
RandomAccessJarFile
URLs can be used with Java’s URLClassLoader
.
The org.springframework.boot.loader.Launcher
class is a special bootstrap class that
is used as an executable jars main entry point. It is the actual Main-Class
in your jar
file and it’s used to setup an appropriate URLClassLoader
and ultimately call your
main()
method.
There are 3 launcher subclasses (JarLauncher
, WarLauncher
and PropertiesLauncher
).
Their purpose is to load resources (.class
files etc.) from nested jar files or war
files in directories (as opposed to explicitly on the classpath). In the case of the
[Jar|War]Launcher
the nested paths are fixed (lib/*.jar
and lib-provided/*.jar
for
the war case) so you just add extra jars in those locations if you want more. The
PropertiesLauncher
looks in lib/
by default, but you can add additional locations by
setting an environment variable LOADER_PATH
or loader.path
in application.properties
(comma-separated list of directories or archives).
You need to specify an appropriate Launcher
as the Main-Class
attribute of
META-INF/MANIFEST.MF
. The actual class that you want to launch (i.e. the class that
you wrote that contains a main
method) should be specified in the Start-Class
attribute.
For example, here is a typical MANIFEST.MF
for an executable jar file:
Main-Class: org.springframework.boot.loader.JarLauncher Start-Class: com.mycompany.project.MyApplication
For a war file, it would be:
Main-Class: org.springframework.boot.loader.WarLauncher Start-Class: com.mycompany.project.MyApplication
Note | |
---|---|
You do not need to specify |
PropertiesLauncher
has a few special features that can be enabled with external
properties (System properties, environment variables, manifest entries or
application.properties
).
Key | Purpose |
---|---|
| Comma-separated Classpath, e.g. |
| Location of additional properties file, e.g. |
| Default arguments for the main method (space separated) |
| Name of main class to launch, e.g. |
| Name of properties file, e.g. |
| Path to properties file, e.g. |
| Boolean flag to indicate that all properties should be added to System properties
(defaults to |
Manifest entry keys are formed by capitalizing initial letters of words and changing the
separator to "-
" from ".
" (e.g. Loader-Path
). The exception is loader.main
which
is looked up as Start-Class
in the manifest for compatibility with JarLauncher
).
Environment variables can be capitalized with underscore separators instead of periods.
loader.home
is the directory location of an additional properties file (overriding
the default) as long as loader.config.location
is not specified.
loader.path
can contain directories (scanned recursively for jar and zip files),
archive paths, or wildcard patterns (for the default JVM behavior).
There are a number of restrictions that you need to consider when working with a Spring Boot Loader packaged application.
The ZipEntry
for a nested jar must be saved using the ZipEntry.STORED
method. This
is required so that we can seek directly to individual content within the nested jar.
The content of the nested jar file itself can still be compressed, as can any other
entries in the outer jar.
Launched applications should use Thread.getContextClassLoader()
when loading classes
(most libraries and frameworks will do this by default). Trying to load nested jar
classes via ClassLoader.getSystemClassLoader()
will fail. Please be aware that
java.util.Logging
always uses the system classloader, for this reason you should
consider a different logging implementation.
If the above restrictions mean that you cannot use Spring Boot Loader the following alternatives could be considered:
The table below provides details of all of the dependency versions that are provided by Spring Boot in its CLI, Maven dependency management and Gradle plugin. When you declare a dependency on one of these artifacts without declaring a version the version that is listed in the table will be used.
Group ID | Artifact ID | Version |
ch.qos.logback | logback-classic | 1.1.2 |
com.codahale.metrics | metrics-core | 3.0.2 |
com.codahale.metrics | metrics-ganglia | 3.0.2 |
com.codahale.metrics | metrics-graphite | 3.0.2 |
com.codahale.metrics | metrics-servlets | 3.0.2 |
com.fasterxml.jackson.core | jackson-annotations | 2.3.3 |
com.fasterxml.jackson.core | jackson-core | 2.3.3 |
com.fasterxml.jackson.core | jackson-databind | 2.3.3 |
com.fasterxml.jackson.datatype | jackson-datatype-joda | 2.3.3 |
com.gemstone.gemfire | gemfire | 7.0.2 |
com.h2database | h2 | 1.3.175 |
com.zaxxer | HikariCP | 1.3.8 |
commons-beanutils | commons-beanutils | 1.9.1 |
commons-collections | commons-collections | 3.2.1 |
commons-dbcp | commons-dbcp | 1.4 |
commons-digester | commons-digester | 2.1 |
commons-pool | commons-pool | 1.6 |
javax.jms | jms-api | 1.1-rev-1 |
javax.servlet | javax.servlet-api | 3.0.1 |
javax.servlet | jstl | 1.2 |
joda-time | joda-time | 2.3 |
junit | junit | 4.11 |
log4j | log4j | 1.2.17 |
mysql | mysql-connector-java | 5.1.30 |
nz.net.ultraq.thymeleaf | thymeleaf-layout-dialect | 1.2.4 |
org.apache.activemq | activemq-broker | 5.9.1 |
org.apache.activemq | activemq-client | 5.9.1 |
org.apache.activemq | activemq-pool | 5.9.1 |
org.apache.commons | commons-pool2 | 2.2 |
org.apache.httpcomponents | httpasyncclient | 4.0.1 |
org.apache.httpcomponents | httpclient | 4.3.3 |
org.apache.httpcomponents | httpmime | 4.3.3 |
org.apache.solr | solr-solrj | 4.7.2 |
org.apache.tomcat | tomcat-jdbc | 7.0.54 |
org.apache.tomcat | tomcat-jsp-api | 7.0.54 |
org.apache.tomcat.embed | tomcat-embed-core | 7.0.54 |
org.apache.tomcat.embed | tomcat-embed-el | 7.0.54 |
org.apache.tomcat.embed | tomcat-embed-jasper | 7.0.54 |
org.apache.tomcat.embed | tomcat-embed-logging-juli | 7.0.54 |
org.apache.tomcat.embed | tomcat-embed-websocket | 7.0.54 |
org.apache.velocity | velocity | 1.7 |
org.apache.velocity | velocity-tools | 2.0 |
org.aspectj | aspectjrt | 1.8.0 |
org.aspectj | aspectjtools | 1.8.0 |
org.aspectj | aspectjweaver | 1.8.0 |
org.codehaus.groovy | groovy | 2.3.2 |
org.codehaus.groovy | groovy-all | 2.3.2 |
org.codehaus.groovy | groovy-ant | 2.3.2 |
org.codehaus.groovy | groovy-bsf | 2.3.2 |
org.codehaus.groovy | groovy-console | 2.3.2 |
org.codehaus.groovy | groovy-docgenerator | 2.3.2 |
org.codehaus.groovy | groovy-groovydoc | 2.3.2 |
org.codehaus.groovy | groovy-groovysh | 2.3.2 |
org.codehaus.groovy | groovy-jmx | 2.3.2 |
org.codehaus.groovy | groovy-json | 2.3.2 |
org.codehaus.groovy | groovy-jsr223 | 2.3.2 |
org.codehaus.groovy | groovy-nio | 2.3.2 |
org.codehaus.groovy | groovy-servlet | 2.3.2 |
org.codehaus.groovy | groovy-sql | 2.3.2 |
org.codehaus.groovy | groovy-swing | 2.3.2 |
org.codehaus.groovy | groovy-templates | 2.3.2 |
org.codehaus.groovy | groovy-test | 2.3.2 |
org.codehaus.groovy | groovy-testng | 2.3.2 |
org.codehaus.groovy | groovy-xml | 2.3.2 |
org.crashub | crash.cli | 1.3.0-beta20 |
org.crashub | crash.connectors.ssh | 1.3.0-beta20 |
org.crashub | crash.connectors.telnet | 1.3.0-beta20 |
org.crashub | crash.embed.spring | 1.3.0-beta20 |
org.crashub | crash.plugins.cron | 1.3.0-beta20 |
org.crashub | crash.plugins.mail | 1.3.0-beta20 |
org.crashub | crash.shell | 1.3.0-beta20 |
org.eclipse.jetty | jetty-annotations | 8.1.14.v20131031 |
org.eclipse.jetty | jetty-jsp | 8.1.14.v20131031 |
org.eclipse.jetty | jetty-util | 8.1.14.v20131031 |
org.eclipse.jetty | jetty-webapp | 8.1.14.v20131031 |
org.eclipse.jetty.orbit | javax.servlet.jsp | 2.2.0.v201112011158 |
org.flywaydb | flyway-core | 3.0 |
org.freemarker | freemarker | 2.3.20 |
org.hamcrest | hamcrest-core | 1.3 |
org.hamcrest | hamcrest-library | 1.3 |
org.hibernate | hibernate-entitymanager | 4.3.1.Final |
org.hibernate | hibernate-validator | 5.0.3.Final |
org.hibernate.javax.persistence | hibernate-jpa-2.0-api | 1.0.1.Final |
org.hornetq | hornetq-jms-client | 2.4.1.Final |
org.hornetq | hornetq-jms-server | 2.4.1.Final |
org.hsqldb | hsqldb | 2.3.2 |
org.javassist | javassist | 3.18.1-GA |
org.jolokia | jolokia-core | 1.2.0 |
org.liquibase | liquibase-core | 3.0.8 |
org.mockito | mockito-core | 1.9.5 |
org.mongodb | mongo-java-driver | 2.12.1 |
org.projectreactor | reactor-core | 1.1.1.RELEASE |
org.projectreactor | reactor-groovy | 1.1.1.RELEASE |
org.projectreactor | reactor-groovy-extensions | 1.1.1.RELEASE |
org.projectreactor | reactor-logback | 1.1.1.RELEASE |
org.projectreactor | reactor-net | 1.1.1.RELEASE |
org.projectreactor.spring | reactor-spring-context | 1.1.1.RELEASE |
org.projectreactor.spring | reactor-spring-core | 1.1.1.RELEASE |
org.projectreactor.spring | reactor-spring-messaging | 1.1.1.RELEASE |
org.projectreactor.spring | reactor-spring-webmvc | 1.1.1.RELEASE |
org.slf4j | jcl-over-slf4j | 1.7.7 |
org.slf4j | jul-to-slf4j | 1.7.7 |
org.slf4j | log4j-over-slf4j | 1.7.7 |
org.slf4j | slf4j-api | 1.7.7 |
org.slf4j | slf4j-jdk14 | 1.7.7 |
org.slf4j | slf4j-log4j12 | 1.7.7 |
org.spockframework | spock-core | 0.7-groovy-2.0 |
org.springframework | spring-aop | 4.0.5.RELEASE |
org.springframework | spring-aspects | 4.0.5.RELEASE |
org.springframework | spring-beans | 4.0.5.RELEASE |
org.springframework | spring-context | 4.0.5.RELEASE |
org.springframework | spring-context-support | 4.0.5.RELEASE |
org.springframework | spring-core | 4.0.5.RELEASE |
org.springframework | spring-expression | 4.0.5.RELEASE |
org.springframework | spring-instrument | 4.0.5.RELEASE |
org.springframework | spring-instrument-tomcat | 4.0.5.RELEASE |
org.springframework | spring-jdbc | 4.0.5.RELEASE |
org.springframework | spring-jms | 4.0.5.RELEASE |
org.springframework | springloaded | 1.2.0.RELEASE |
org.springframework | spring-messaging | 4.0.5.RELEASE |
org.springframework | spring-orm | 4.0.5.RELEASE |
org.springframework | spring-oxm | 4.0.5.RELEASE |
org.springframework | spring-test | 4.0.5.RELEASE |
org.springframework | spring-tx | 4.0.5.RELEASE |
org.springframework | spring-web | 4.0.5.RELEASE |
org.springframework | spring-webmvc | 4.0.5.RELEASE |
org.springframework | spring-webmvc-portlet | 4.0.5.RELEASE |
org.springframework | spring-websocket | 4.0.5.RELEASE |
org.springframework.amqp | spring-amqp | 1.3.4.RELEASE |
org.springframework.amqp | spring-erlang | 1.3.4.RELEASE |
org.springframework.amqp | spring-rabbit | 1.3.4.RELEASE |
org.springframework.batch | spring-batch-core | 3.0.0.RELEASE |
org.springframework.batch | spring-batch-infrastructure | 3.0.0.RELEASE |
org.springframework.batch | spring-batch-integration | 3.0.0.RELEASE |
org.springframework.batch | spring-batch-test | 3.0.0.RELEASE |
org.springframework.boot | spring-boot | 1.1.0.RC1 |
org.springframework.boot | spring-boot | 1.1.0.RC1 |
org.springframework.boot | spring-boot-actuator | 1.1.0.RC1 |
org.springframework.boot | spring-boot-autoconfigure | 1.1.0.RC1 |
org.springframework.boot | spring-boot-dependency-tools | 1.1.0.RC1 |
org.springframework.boot | spring-boot-loader | 1.1.0.RC1 |
org.springframework.boot | spring-boot-loader-tools | 1.1.0.RC1 |
org.springframework.boot | spring-boot-starter | 1.1.0.RC1 |
org.springframework.boot | spring-boot-starter-actuator | 1.1.0.RC1 |
org.springframework.boot | spring-boot-starter-amqp | 1.1.0.RC1 |
org.springframework.boot | spring-boot-starter-aop | 1.1.0.RC1 |
org.springframework.boot | spring-boot-starter-batch | 1.1.0.RC1 |
org.springframework.boot | spring-boot-starter-data-elasticsearch | 1.1.0.RC1 |
org.springframework.boot | spring-boot-starter-data-gemfire | 1.1.0.RC1 |
org.springframework.boot | spring-boot-starter-data-jpa | 1.1.0.RC1 |
org.springframework.boot | spring-boot-starter-data-mongodb | 1.1.0.RC1 |
org.springframework.boot | spring-boot-starter-data-rest | 1.1.0.RC1 |
org.springframework.boot | spring-boot-starter-data-solr | 1.1.0.RC1 |
org.springframework.boot | spring-boot-starter-freemarker | 1.1.0.RC1 |
org.springframework.boot | spring-boot-starter-groovy-templates | 1.1.0.RC1 |
org.springframework.boot | spring-boot-starter-hornetq | 1.1.0.RC1 |
org.springframework.boot | spring-boot-starter-integration | 1.1.0.RC1 |
org.springframework.boot | spring-boot-starter-jdbc | 1.1.0.RC1 |
org.springframework.boot | spring-boot-starter-jetty | 1.1.0.RC1 |
org.springframework.boot | spring-boot-starter-log4j | 1.1.0.RC1 |
org.springframework.boot | spring-boot-starter-logging | 1.1.0.RC1 |
org.springframework.boot | spring-boot-starter-mobile | 1.1.0.RC1 |
org.springframework.boot | spring-boot-starter-redis | 1.1.0.RC1 |
org.springframework.boot | spring-boot-starter-remote-shell | 1.1.0.RC1 |
org.springframework.boot | spring-boot-starter-security | 1.1.0.RC1 |
org.springframework.boot | spring-boot-starter-social-facebook | 1.1.0.RC1 |
org.springframework.boot | spring-boot-starter-social-linkedin | 1.1.0.RC1 |
org.springframework.boot | spring-boot-starter-social-twitter | 1.1.0.RC1 |
org.springframework.boot | spring-boot-starter-test | 1.1.0.RC1 |
org.springframework.boot | spring-boot-starter-thymeleaf | 1.1.0.RC1 |
org.springframework.boot | spring-boot-starter-tomcat | 1.1.0.RC1 |
org.springframework.boot | spring-boot-starter-velocity | 1.1.0.RC1 |
org.springframework.boot | spring-boot-starter-web | 1.1.0.RC1 |
org.springframework.boot | spring-boot-starter-websocket | 1.1.0.RC1 |
org.springframework.data | spring-data-cassandra | 1.0.0.RELEASE |
org.springframework.data | spring-data-commons | 1.8.0.RELEASE |
org.springframework.data | spring-data-couchbase | 1.1.0.RELEASE |
org.springframework.data | spring-data-elasticsearch | 1.0.0.RELEASE |
org.springframework.data | spring-data-gemfire | 1.4.0.RELEASE |
org.springframework.data | spring-data-jpa | 1.6.0.RELEASE |
org.springframework.data | spring-data-mongodb | 1.5.0.RELEASE |
org.springframework.data | spring-data-neo4j | 3.1.0.RELEASE |
org.springframework.data | spring-data-redis | 1.3.0.RELEASE |
org.springframework.data | spring-data-rest-webmvc | 2.1.0.RELEASE |
org.springframework.data | spring-data-solr | 1.2.0.RELEASE |
org.springframework.hateoas | spring-hateoas | 0.12.0.RELEASE |
org.springframework.integration | spring-integration-amqp | 4.0.2.RELEASE |
org.springframework.integration | spring-integration-core | 4.0.2.RELEASE |
org.springframework.integration | spring-integration-event | 4.0.2.RELEASE |
org.springframework.integration | spring-integration-feed | 4.0.2.RELEASE |
org.springframework.integration | spring-integration-file | 4.0.2.RELEASE |
org.springframework.integration | spring-integration-ftp | 4.0.2.RELEASE |
org.springframework.integration | spring-integration-gemfire | 4.0.2.RELEASE |
org.springframework.integration | spring-integration-groovy | 4.0.2.RELEASE |
org.springframework.integration | spring-integration-http | 4.0.2.RELEASE |
org.springframework.integration | spring-integration-ip | 4.0.2.RELEASE |
org.springframework.integration | spring-integration-jdbc | 4.0.2.RELEASE |
org.springframework.integration | spring-integration-jms | 4.0.2.RELEASE |
org.springframework.integration | spring-integration-jmx | 4.0.2.RELEASE |
org.springframework.integration | spring-integration-jpa | 4.0.2.RELEASE |
org.springframework.integration | spring-integration-mail | 4.0.2.RELEASE |
org.springframework.integration | spring-integration-mongodb | 4.0.2.RELEASE |
org.springframework.integration | spring-integration-mqtt | 4.0.2.RELEASE |
org.springframework.integration | spring-integration-redis | 4.0.2.RELEASE |
org.springframework.integration | spring-integration-rmi | 4.0.2.RELEASE |
org.springframework.integration | spring-integration-scripting | 4.0.2.RELEASE |
org.springframework.integration | spring-integration-security | 4.0.2.RELEASE |
org.springframework.integration | spring-integration-sftp | 4.0.2.RELEASE |
org.springframework.integration | spring-integration-stream | 4.0.2.RELEASE |
org.springframework.integration | spring-integration-syslog | 4.0.2.RELEASE |
org.springframework.integration | spring-integration-test | 4.0.2.RELEASE |
org.springframework.integration | spring-integration-twitter | 4.0.2.RELEASE |
org.springframework.integration | spring-integration-ws | 4.0.2.RELEASE |
org.springframework.integration | spring-integration-xml | 4.0.2.RELEASE |
org.springframework.integration | spring-integration-xmpp | 4.0.2.RELEASE |
org.springframework.mobile | spring-mobile-device | 1.1.1.RELEASE |
org.springframework.security | spring-security-acl | 3.2.4.RELEASE |
org.springframework.security | spring-security-aspects | 3.2.4.RELEASE |
org.springframework.security | spring-security-cas | 3.2.4.RELEASE |
org.springframework.security | spring-security-config | 3.2.4.RELEASE |
org.springframework.security | spring-security-core | 3.2.4.RELEASE |
org.springframework.security | spring-security-crypto | 3.2.4.RELEASE |
org.springframework.security | spring-security-jwt | 1.0.2.RELEASE |
org.springframework.security | spring-security-ldap | 3.2.4.RELEASE |
org.springframework.security | spring-security-openid | 3.2.4.RELEASE |
org.springframework.security | spring-security-remoting | 3.2.4.RELEASE |
org.springframework.security | spring-security-taglibs | 3.2.4.RELEASE |
org.springframework.security | spring-security-web | 3.2.4.RELEASE |
org.springframework.social | spring-social-config | 1.1.0.RELEASE |
org.springframework.social | spring-social-core | 1.1.0.RELEASE |
org.springframework.social | spring-social-facebook | 1.1.1.RELEASE |
org.springframework.social | spring-social-facebook-web | 1.1.1.RELEASE |
org.springframework.social | spring-social-linkedin | 1.0.1.RELEASE |
org.springframework.social | spring-social-security | 1.1.0.RELEASE |
org.springframework.social | spring-social-twitter | 1.1.0.RELEASE |
org.springframework.social | spring-social-web | 1.1.0.RELEASE |
org.thymeleaf | thymeleaf | 2.1.3.RELEASE |
org.thymeleaf | thymeleaf-spring4 | 2.1.3.RELEASE |
org.thymeleaf.extras | thymeleaf-extras-springsecurity3 | 2.1.1.RELEASE |
org.yaml | snakeyaml | 1.13 |
redis.clients | jedis | 2.4.1 |