Spring Boot can be used with “classic” Java development tools or installed as a command line tool. Either way, you need Java SDK v1.8 or higher. Before you begin, you should check your current Java installation by using the following command:
$ java -version
If you are new to Java development or if you want to experiment with Spring Boot, you might want to try the Spring Boot CLI (Command Line Interface) first. Otherwise, read on for “classic” installation instructions.
You can use Spring Boot in the same way as any standard Java library. To do so, 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. Also, there
is nothing special about a Spring Boot application, so you can run and debug a Spring
Boot application as you would any other Java program.
Although you could 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 3.3 or above. If you do not already have Maven installed, you can follow the instructions at maven.apache.org.
Tip | |
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On many operating systems, Maven can be installed with a package manager. If you use
OSX Homebrew, try |
Spring Boot dependencies use the org.springframework.boot
groupId
. Typically, your
Maven POM file inherits from the spring-boot-starter-parent
project and declares
dependencies to one or more “Starters”.
Spring Boot also provides an optional
Maven plugin to create
executable jars.
The following listing shows 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>2.1.0.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>https://repo.spring.io/snapshot</url> <snapshots><enabled>true</enabled></snapshots> </repository> <repository> <id>spring-milestones</id> <url>https://repo.spring.io/milestone</url> </repository> </repositories> <pluginRepositories> <pluginRepository> <id>spring-snapshots</id> <url>https://repo.spring.io/snapshot</url> </pluginRepository> <pluginRepository> <id>spring-milestones</id> <url>https://repo.spring.io/milestone</url> </pluginRepository> </pluginRepositories> </project>
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The |
Spring Boot is compatible with Gradle 4.4 and later. If you do not already have Gradle installed, you can follow the instructions at gradle.org.
Spring Boot dependencies can be declared by using the org.springframework.boot
group
.
Typically, your project declares dependencies to one or more
“Starters”. Spring Boot
provides a useful Gradle
plugin that can be used to simplify dependency declarations and to create executable
jars.
The following example shows a typical build.gradle
file:
buildscript { repositories { jcenter() maven { url 'https://repo.spring.io/snapshot' } maven { url 'https://repo.spring.io/milestone' } } dependencies { classpath 'org.springframework.boot:spring-boot-gradle-plugin:2.1.0.RC1' } } apply plugin: 'java' apply plugin: 'org.springframework.boot' apply plugin: 'io.spring.dependency-management' jar { baseName = 'myproject' version = '0.0.1-SNAPSHOT' } repositories { jcenter() maven { url "https://repo.spring.io/snapshot" } maven { url "https://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 (Command Line Interface) is a command line tool that you can use to quickly prototype with Spring. It lets you run Groovy scripts, which means that you have a familiar Java-like syntax without so much boilerplate code.
You do not need to use the CLI to work with Spring Boot, but it is 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. Alternatively, you
can use java -jar
with the .jar
file (the script helps you to be sure that the
classpath is set correctly).
SDKMAN! (The Software Development Kit Manager) can be used for managing multiple versions of various binary SDKs, including Groovy and the Spring Boot CLI. Get SDKMAN! from sdkman.io and install Spring Boot by using the following commands:
$ sdk install springboot $ spring --version Spring Boot v2.1.0.RC1
If you develop features for the CLI and want easy access to the version you built, use the following commands:
$ sdk install springboot dev /path/to/spring-boot/spring-boot-cli/target/spring-boot-cli-2.1.0.RC1-bin/spring-2.1.0.RC1/ $ sdk default springboot dev $ spring --version Spring CLI v2.1.0.RC1
The preceding instructions install a local instance of spring
called the dev
instance. It points at your target build location, so every time you rebuild Spring Boot,
spring
is up-to-date.
You can see it by running the following command:
$ sdk ls springboot ================================================================================ Available Springboot Versions ================================================================================ > + dev * 2.1.0.RC1 ================================================================================ + - local version * - installed > - currently in use ================================================================================
If you are on a Mac and use Homebrew, you can install the Spring Boot CLI by using the following commands:
$ brew tap pivotal/tap $ brew install springboot
Homebrew installs spring
to /usr/local/bin
.
Note | |
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If you do not see the formula, your installation of brew might be out-of-date. In
that case, run |
If you are on a Mac and use MacPorts, you can install the Spring Boot CLI by using the following command:
$ sudo port install spring-boot-cli
The Spring Boot CLI includes scripts that provide command completion for the
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. For example, to run the script manually if you have installed by using SDKMAN!,
use the following commands:
$ . ~/.sdkman/candidates/springboot/current/shell-completion/bash/spring $ spring <HIT TAB HERE> grab help jar run test version
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If you install the Spring Boot CLI by using Homebrew or MacPorts, the command-line completion scripts are automatically registered with your shell. |
If you are on a Windows and use Scoop, you can install the Spring Boot CLI by using the following commands:
> scoop bucket add extras > scoop install springboot
Scoop installs spring
to ~/scoop/apps/springboot/current/bin
.
Note | |
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If you do not see the app manifest, your installation of scoop might be out-of-date.
In that case, run |
You can use the following web application to test your installation. To start, create a
file called app.groovy
, as follows:
@RestController class ThisWillActuallyRun { @RequestMapping("/") String home() { "Hello World!" } }
Then run it from a shell, as follows:
$ spring run app.groovy
Note | |
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The first run of your application is slow, as dependencies are downloaded. Subsequent runs are much quicker. |
Open localhost:8080
in your favorite web browser. You should see the following
output:
Hello World!
If you are upgrading from an earlier release of Spring Boot, check the “migration guide” on the project wiki that provides detailed upgrade instructions. Check also the “release notes” for a list of “new and noteworthy” features for each release.
When upgrading to a new feature release, some properties may have been renamed or removed. Spring Boot provides a way to analyze your application’s environment and print diagnostics at startup, but also temporarily migrate properties at runtime for you. To enable that feature, add the following dependency to your project:
<dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-properties-migrator</artifactId> <scope>runtime</scope> </dependency>
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Properties that are added late to the environment, such as when using
|
Note | |
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Once you’re done with the migration, please make sure to remove this module from your project’s dependencies. |
To upgrade an existing CLI installation, use the appropriate package manager command (for
example, brew upgrade
) or, if you manually installed the CLI, follow the
standard instructions, remembering to update
your PATH
environment variable to remove any older references.