1. Introduction
The Spring Boot Maven Plugin provides Spring Boot support in Apache Maven. It allows you to package executable jar or war archives, run Spring Boot applications, generate build information and start your Spring Boot application prior to running integration tests.
2. Getting started
The Spring Boot Plugin has the following goals:
| Goal | Description |
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Package an application into a OCI image using a buildpack. |
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Generate a |
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Display help information on spring-boot-maven-plugin. Call |
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Repackage existing JAR and WAR archives so that they can be executed from the command line using |
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Run an application in place. |
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Start a spring application. Contrary to the |
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Stop an application that has been started by the "start" goal. Typically invoked once a test suite has completed. |
3. Packaging executable archives
The plugin can create executable archives (jar files and war files) that contain all of an application’s dependencies and can then be run with java -jar.
Packaging an executable archive is performed by the repackage goal, as shown in the following example:
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
<version>2.3.0.M1</version>
<executions>
<execution>
<goals>
<goal>repackage</goal>
</goals>
</execution>
</executions>
</plugin>
</plugins>
</build>
If you are using spring-boot-starter-parent, such execution is already pre-configured with a repackage execution id so that only the plugin definition should be added.
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The example above repackages a jar or war that is built during the package phase of the Maven lifecycle, including any provided dependencies that are defined in the project.
If some of these dependencies need to be excluded, you can use one of the exclude options, see the dependency exclusion for more details.
The outputFileNameMapping feature of the maven-war-plugin is currently not supported.
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Devtools is automatically excluded by default (you can control that using the excludeDevtools property).
In order to make that work with war packaging, the spring-boot-devtools dependency must be set as optional or with the provided scope.
The original (i.e. non executable) artifact is renamed to .original by default but it is also possible to keep the original artifact using a custom classifier.
The plugin rewrites your manifest, and in particular it manages the "Main-Class" and "Start-Class" entries, so if the defaults don’t work you have to configure those there (not in the jar plugin). The "Main-Class" in the manifest is actually controlled by the "layout" property of the Spring Boot plugin, as shown in the following example:
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
<version>2.3.0.M1</version>
<configuration>
<mainClass>${start.class}</mainClass>
<layout>ZIP</layout>
</configuration>
<executions>
<execution>
<goals>
<goal>repackage</goal>
</goals>
</execution>
</executions>
</plugin>
</plugins>
</build>The layout property defaults to a guess based on the archive type (jar or war). The following layouts are available:
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JAR: regular executable JAR layout. -
WAR: executable WAR layout.provideddependencies are placed inWEB-INF/lib-providedto avoid any clash when thewaris deployed in a servlet container. -
ZIP(alias toDIR): similar to theJARlayout usingPropertiesLauncher. -
NONE: Bundle all dependencies and project resources. Does not bundle a bootstrap loader.
3.1. spring-boot:repackage
org.springframework.boot:spring-boot-maven-plugin:2.3.0.M1
Repackage existing JAR and WAR archives so that they can be executed from the command line using java -jar. With layout=NONE can also be used simply to package a JAR with nested dependencies (and no main class, so not executable).
3.1.1. Required parameters
| Name | Type | Default |
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3.1.2. Optional parameters
| Name | Type | Default |
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3.1.3. Parameter details
attach
Attach the repackaged archive to be installed into your local Maven repository or deployed to a remote repository. If no classifier has been configured, it will replace the normal jar. If a classifier has been configured such that the normal jar and the repackaged jar are different, it will be attached alongside the normal jar. When the property is set to false, the repackaged archive will not be installed or deployed.
Name |
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|---|---|
Type |
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Default value |
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User property |
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Since |
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classifier
Classifier to add to the repackaged archive. If not given, the main artifact will be replaced by the repackaged archive. If given, the classifier will also be used to determine the source archive to repackage: if an artifact with that classifier already exists, it will be used as source and replaced. If no such artifact exists, the main artifact will be used as source and the repackaged archive will be attached as a supplemental artifact with that classifier. Attaching the artifact allows to deploy it alongside to the original one, see $1[$2].
Name |
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|---|---|
Type |
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Default value |
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User property |
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Since |
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embeddedLaunchScript
The embedded launch script to prepend to the front of the jar if it is fully executable. If not specified the 'Spring Boot' default script will be used.
Name |
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|---|---|
Type |
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Default value |
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User property |
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Since |
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embeddedLaunchScriptProperties
Properties that should be expanded in the embedded launch script.
Name |
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|---|---|
Type |
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Default value |
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User property |
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Since |
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excludeDevtools
Exclude Spring Boot devtools from the repackaged archive.
Name |
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|---|---|
Type |
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Default value |
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User property |
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Since |
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excludeGroupIds
Comma separated list of groupId names to exclude (exact match).
Name |
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|---|---|
Type |
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Default value |
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User property |
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Since |
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excludes
Collection of artifact definitions to exclude. The Exclude element defines a groupId and artifactId mandatory properties and an optional classifier property.
Name |
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|---|---|
Type |
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Default value |
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User property |
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Since |
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executable
Make a fully executable jar for *nix machines by prepending a launch script to the jar. <p> Currently, some tools do not accept this format so you may not always be able to use this technique. For example, jar -xf may silently fail to extract a jar or war that has been made fully-executable. It is recommended that you only enable this option if you intend to execute it directly, rather than running it with java -jar or deploying it to a servlet container.
Name |
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|---|---|
Type |
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Default value |
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User property |
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Since |
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includeSystemScope
Include system scoped dependencies.
Name |
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|---|---|
Type |
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Default value |
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User property |
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Since |
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includes
Collection of artifact definitions to include. The Include element defines a groupId and artifactId mandatory properties and an optional classifier property.
Name |
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|---|---|
Type |
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Default value |
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User property |
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Since |
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layout
The type of archive (which corresponds to how the dependencies are laid out inside it). Possible values are JAR, LAYERED_JAR, WAR, ZIP, DIR, NONE. Defaults to a guess based on the archive type.
Name |
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|---|---|
Type |
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Default value |
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User property |
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Since |
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layoutFactory
The layout factory that will be used to create the executable archive if no explicit layout is set. Alternative layouts implementations can be provided by 3rd parties.
Name |
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|---|---|
Type |
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Default value |
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User property |
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Since |
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mainClass
The name of the main class. If not specified the first compiled class found that contains a 'main' method will be used.
Name |
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|---|---|
Type |
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Default value |
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User property |
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Since |
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outputDirectory
Directory containing the generated archive.
Name |
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|---|---|
Type |
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Default value |
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User property |
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Since |
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requiresUnpack
A list of the libraries that must be unpacked from fat jars in order to run. Specify each library as a <dependency> with a <groupId> and a <artifactId> and they will be unpacked at runtime.
Name |
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Type |
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Default value |
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User property |
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Since |
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skip
Skip the execution.
Name |
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|---|---|
Type |
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Default value |
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User property |
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Since |
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3.2. Examples
3.2.1. Custom Classifier
By default, the repackage goal replaces the original artifact with the repackaged one.
That is a sane behavior for modules that represent an application but if your module is used as a dependency of another module, you need to provide a classifier for the repackaged one.
The reason for that is that application classes are packaged in BOOT-INF/classes so that the dependent module cannot load a repackaged jar’s classes.
If that is the case or if you prefer to keep the original artifact and attach the repackaged one with a different classifier, configure the plugin as shown in the following example:
<project>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
<version>2.3.0.M1</version>
<executions>
<execution>
<id>repackage</id>
<goals>
<goal>repackage</goal>
</goals>
<configuration>
<classifier>exec</classifier>
</configuration>
</execution>
</executions>
</plugin>
</plugins>
</build>
</project>If you are using spring-boot-starter-parent, the repackage goal is executed automatically in an execution with id repackage.
In that setup, only the configuration should be specified, as shown in the following example:
<project>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
<executions>
<execution>
<id>repackage</id>
<configuration>
<classifier>exec</classifier>
</configuration>
</execution>
</executions>
</plugin>
</plugins>
</build>
</project>This configuration will generate two artifacts: the original one and the repackaged counter part produced by the repackage goal. Both will be installed/deployed transparently.
You can also use the same configuration if you want to repackage a secondary artifact the same way the main artifact is replaced.
The following configuration installs/deploys a single task classified artifact with the repackaged application:
<project>
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-jar-plugin</artifactId>
<version>1.2.3</version>
<executions>
<execution>
<goals>
<goal>jar</goal>
</goals>
<phase>package</phase>
<configuration>
<classifier>task</classifier>
</configuration>
</execution>
</executions>
</plugin>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
<version>2.3.0.M1</version>
<executions>
<execution>
<id>repackage</id>
<goals>
<goal>repackage</goal>
</goals>
<configuration>
<classifier>task</classifier>
</configuration>
</execution>
</executions>
</plugin>
</plugins>
</build>
</project>As both the maven-jar-plugin and the spring-boot-maven-plugin runs at the same phase, it is important that the jar plugin is defined first (so that it runs before the repackage goal).
Again, if you are using spring-boot-starter-parent, this can be simplified as follows:
<project>
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-jar-plugin</artifactId>
<executions>
<execution>
<id>default-jar</id>
<configuration>
<classifier>task</classifier>
</configuration>
</execution>
</executions>
</plugin>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
<executions>
<execution>
<id>repackage</id>
<configuration>
<classifier>task</classifier>
</configuration>
</execution>
</executions>
</plugin>
</plugins>
</build>
</project>3.2.2. Custom Name
If you need the repackaged jar to have a different local name than the one defined by the artifactId attribute of the project, simply use the standard finalName, as shown in the following example:
<project>
<build>
<finalName>my-app</finalName>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
<version>2.3.0.M1</version>
<executions>
<execution>
<id>repackage</id>
<goals>
<goal>repackage</goal>
</goals>
</execution>
</executions>
</plugin>
</plugins>
</build>
</project>This configuration will generate the repackaged artifact in target/my-app.jar.
3.2.3. Local Repackaged Artifact
By default, the repackage goal replaces the original artifact with the executable one.
If you need to only deploy the original jar and yet be able to run your app with the regular file name, configure the plugin as follows:
<project>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
<version>2.3.0.M1</version>
<executions>
<execution>
<id>repackage</id>
<goals>
<goal>repackage</goal>
</goals>
<configuration>
<attach>false</attach>
</configuration>
</execution>
</executions>
</plugin>
</plugins>
</build>
</project>This configuration generates two artifacts: the original one and the executable counter part produced by the repackage goal.
Only the original one will be installed/deployed.
3.2.4. Custom Layout
Spring Boot repackages the jar file for this project using a custom layout factory defined in the additional jar file, provided as a dependency to the build plugin:
<project>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
<version>2.3.0.M1</version>
<executions>
<execution>
<id>repackage</id>
<goals>
<goal>repackage</goal>
</goals>
<configuration>
<layoutFactory implementation="com.example.CustomLayoutFactory">
<customProperty>value</customProperty>
</layoutFactory>
</configuration>
</execution>
</executions>
<dependencies>
<dependency>
<groupId>com.example</groupId>
<artifactId>custom-layout</artifactId>
<version>0.0.1.BUILD-SNAPSHOT</version>
</dependency>
</dependencies>
</plugin>
</plugins>
</build>
</project>The layout factory is provided as an implementation of LayoutFactory (from spring-boot-loader-tools) explicitly specified in the pom.
If there is only one custom LayoutFactory on the plugin classpath and it is listed in META-INF/spring.factories then it is unnecessary to explicitly set it in the plugin configuration.
Layout factories are always ignored if an explicit layout is set.
3.2.5. Dependency Exclusion
By default, both the repackage and the run goals will include any provided dependencies that are defined in the project.
A Spring Boot project should consider provided dependencies as "container" dependencies that are required to run the application.
Some of these dependencies may not be required at all and should be excluded from the executable jar. For consistency, they should not be present either when running the application.
There are two ways one can exclude a dependency from being packaged/used at runtime:
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Exclude a specific artifact identified by
groupIdandartifactId, optionally with aclassifierif needed. -
Exclude any artifact belonging to a given
groupId.
The following example excludes com.foo:bar, and only that artifact:
<project>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
<version>2.3.0.M1</version>
<configuration>
<excludes>
<exclude>
<groupId>com.foo</groupId>
<artifactId>bar</artifactId>
</exclude>
</excludes>
</configuration>
</plugin>
</plugins>
</build>
</project>This example excludes any artifact belonging to the com.foo group:
<project>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
<version>2.3.0.M1</version>
<configuration>
<excludeGroupIds>com.foo</excludeGroupIds>
</configuration>
</plugin>
</plugins>
</build>
</project>4. Packaging OCI Images
The plugin can create OCI images using a buildpack.
Images can be built using the build-image goal and a local Docker installation.
It is possible to automate the creation of an image whenever the package phase is invoked, as shown in the following example:
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
<version>{gradle-project-version}</version>
<executions>
<execution>
<goals>
<goal>build-image</goal>
</goals>
</execution>
</executions>
</plugin>
</plugins>
</build>
While the buildpack runs from an executable archive, it is not necessary to execute the repackage goal first as the executable archive is created automatically if necessary.
When the build-image repackages the application, it applies the same settings as the repackage goal would, i.e. dependencies can be excluded using one of the exclude options, and Devtools is automatically excluded by default (you can control that using the excludeDevtools property).
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By default, the image is built using the cloudfoundry/cnb:0.0.43-bionic builder and its name is deduced from the artifactId of the project.
Both these settings can be tuned via configuration, see custom image builder and custom image name.
4.1. spring-boot:build-image
org.springframework.boot:spring-boot-maven-plugin:2.3.0.M1
Package an application into a OCI image using a buildpack.
4.1.1. Required parameters
| Name | Type | Default |
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4.1.2. Optional parameters
| Name | Type | Default |
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4.1.3. Parameter details
classifier
Classifier used when finding the source jar.
Name |
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Type |
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Default value |
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User property |
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Since |
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excludeDevtools
Exclude Spring Boot devtools from the repackaged archive.
Name |
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Type |
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Default value |
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User property |
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Since |
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excludeGroupIds
Comma separated list of groupId names to exclude (exact match).
Name |
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|---|---|
Type |
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Default value |
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User property |
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Since |
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excludes
Collection of artifact definitions to exclude. The Exclude element defines a groupId and artifactId mandatory properties and an optional classifier property.
Name |
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|---|---|
Type |
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Default value |
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User property |
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Since |
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image
Image configuration operations.
Name |
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Type |
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Default value |
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User property |
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Since |
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includeSystemScope
Include system scoped dependencies.
Name |
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Type |
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Default value |
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User property |
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Since |
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includes
Collection of artifact definitions to include. The Include element defines a groupId and artifactId mandatory properties and an optional classifier property.
Name |
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|---|---|
Type |
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Default value |
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User property |
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Since |
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layout
The type of archive (which corresponds to how the dependencies are laid out inside it). Possible values are JAR, LAYERED_JAR, WAR, ZIP, DIR, NONE. Defaults to a guess based on the archive type.
Name |
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|---|---|
Type |
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Default value |
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User property |
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Since |
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layoutFactory
The layout factory that will be used to create the executable archive if no explicit layout is set. Alternative layouts implementations can be provided by 3rd parties.
Name |
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|---|---|
Type |
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Default value |
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User property |
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Since |
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mainClass
The name of the main class. If not specified the first compiled class found that contains a 'main' method will be used.
Name |
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|---|---|
Type |
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Default value |
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User property |
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Since |
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skip
Skip the execution.
Name |
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|---|---|
Type |
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Default value |
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User property |
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Since |
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sourceDirectory
Directory containing the JAR.
Name |
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Type |
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Default value |
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User property |
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Since |
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4.2. Examples
4.2.1. Custom Image Builder
If you need to customize the builder used to create the image, configure yours as shown in the following example:
<project>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
<version>{gradle-project-version}</version>
<executions>
<execution>
<id>build-image</id>
<goals>
<goal>build-image</goal>
</goals>
<configuration>
<image>
<builder>mine/java-cnb-builder</builder>
</image>
</configuration>
</execution>
</executions>
</plugin>
</plugins>
</build>
</project>This configuration will use the latest version of the mine/java-cnb-builder builder.
4.2.2. Custom Image Name
By default, the image name is inferred from the artifactId and the version of the project, something like docker.io/library/${project.artifactId}:{project.version}.
You can take control over the name, as shown in the following example:
<project>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
<version>{gradle-project-version}</version>
<executions>
<execution>
<id>build-image</id>
<goals>
<goal>build-image</goal>
</goals>
<configuration>
<image>
<name>example.com/library/${project.artifactId}</builder>
</image>
</configuration>
</execution>
</executions>
</plugin>
</plugins>
</build>
</project>Note that this configuration does not provide an explicit version so latest is used.
It is possible to specify a version as well, either using ${project.version}, any property available in the build or an hardcoded version.
5. Running your application with Maven
The plugin includes a run goal which can be used to launch your application from the command line, as shown in the following example:
$ mvn spring-boot:run
By default the application is executed in a forked process and setting properties on the command-line will not affect the application.
If you need to specify some JVM arguments (i.e. for debugging purposes), you can use the jvmArguments parameter, see Debug the application for more details.
There is also explicit support for system properties and environment variables.
As enabling a profile is quite common, there is dedicated profiles property that offers a shortcut for -Dspring-boot.run.jvmArguments="-Dspring.profiles.active=dev", see Specify active profiles.
Although this is not recommended, it is possible to execute the application directly from the Maven JVM by disabling the fork property.
Doing so means that the jvmArguments, systemPropertyVariables, environmentVariables and agents options are ignored.
Spring Boot devtools is a module to improve the development-time experience when working on Spring Boot applications.
To enable it, just add the following dependency to your project:
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-devtools</artifactId>
<version>2.3.0.M1</version>
<optional>true</optional>
</dependency>
</dependencies>When devtools is running, it detects change when you recompile your application and automatically refreshes it.
This works for not only resources but code as well.
It also provides a LiveReload server so that it can automatically trigger a browser refresh whenever things change.
Devtools can also be configured to only refresh the browser whenever a static resource has changed (and ignore any change in the code). Just include the following property in your project:
spring.devtools.remote.restart.enabled=falsePrior to devtools, the plugin supported hot refreshing of resources by default which has now be disabled in favour of the solution described above.
You can restore it at any time by configuring your project:
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
<version>2.3.0.M1</version>
<configuration>
<addResources>true</addResources>
</configuration>
</plugin>
</plugins>
</build>When addResources is enabled, any src/main/resources folder will be added to the application classpath when you run the application and any duplicate found in target/classes will be removed.
This allows hot refreshing of resources which can be very useful when developing web applications.
For example, you can work on HTML, CSS or JavaScript files and see your changes immediately without recompiling your application.
It is also a helpful way of allowing your front end developers to work without needing to download and install a Java IDE.
| A side effect of using this feature is that filtering of resources at build time will not work. |
In order to be consistent with the repackage goal, the run goal builds the classpath in such a way that any dependency that is excluded in the plugin’s configuration gets excluded from the classpath as well.
For more details, see the dedicated example.
Sometimes it is useful to include test dependencies when running the application.
For example, if you want to run your application in a test mode that uses stub classes.
If you wish to do this, you can set the useTestClasspath parameter to true.
Note that this is only applied when you run an application: the repackage goal will not add test dependencies to the resulting JAR/WAR.
5.1. spring-boot:run
org.springframework.boot:spring-boot-maven-plugin:2.3.0.M1
Run an application in place.
5.1.1. Required parameters
| Name | Type | Default |
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5.1.2. Optional parameters
| Name | Type | Default |
|---|---|---|
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5.1.3. Parameter details
addResources
Add maven resources to the classpath directly, this allows live in-place editing of resources. Duplicate resources are removed from target/classes to prevent them to appear twice if ClassLoader.getResources() is called. Please consider adding spring-boot-devtools to your project instead as it provides this feature and many more.
Name |
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Type |
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Default value |
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User property |
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Since |
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agents
Path to agent jars. NOTE: a forked process is required to use this feature.
Name |
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|---|---|
Type |
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Default value |
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User property |
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Since |
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arguments
Arguments that should be passed to the application.
Name |
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|---|---|
Type |
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Default value |
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User property |
|
Since |
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classesDirectory
Directory containing the classes and resource files that should be packaged into the archive.
Name |
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|---|---|
Type |
|
Default value |
|
User property |
|
Since |
|
environmentVariables
List of Environment variables that should be associated with the forked process used to run the application. NOTE: a forked process is required to use this feature.
Name |
|
|---|---|
Type |
|
Default value |
|
User property |
|
Since |
|
excludeGroupIds
Comma separated list of groupId names to exclude (exact match).
Name |
|
|---|---|
Type |
|
Default value |
|
User property |
|
Since |
|
excludes
Collection of artifact definitions to exclude. The Exclude element defines a groupId and artifactId mandatory properties and an optional classifier property.
Name |
|
|---|---|
Type |
|
Default value |
|
User property |
|
Since |
|
folders
Additional folders besides the classes directory that should be added to the classpath.
Name |
|
|---|---|
Type |
|
Default value |
|
User property |
|
Since |
|
fork
Flag to indicate if the run processes should be forked. Disabling forking will disable some features such as an agent, custom JVM arguments, devtools or specifying the working directory to use.
Name |
|
|---|---|
Type |
|
Default value |
|
User property |
|
Since |
|
includes
Collection of artifact definitions to include. The Include element defines a groupId and artifactId mandatory properties and an optional classifier property.
Name |
|
|---|---|
Type |
|
Default value |
|
User property |
|
Since |
|
jvmArguments
JVM arguments that should be associated with the forked process used to run the application. On command line, make sure to wrap multiple values between quotes. NOTE: a forked process is required to use this feature.
Name |
|
|---|---|
Type |
|
Default value |
|
User property |
|
Since |
|
mainClass
The name of the main class. If not specified the first compiled class found that contains a 'main' method will be used.
Name |
|
|---|---|
Type |
|
Default value |
|
User property |
|
Since |
|
noverify
Flag to say that the agent requires -noverify.
Name |
|
|---|---|
Type |
|
Default value |
|
User property |
|
Since |
|
optimizedLaunch
Whether the JVM’s launch should be optimized.
Name |
|
|---|---|
Type |
|
Default value |
|
User property |
|
Since |
|
profiles
The spring profiles to activate. Convenience shortcut of specifying the 'spring.profiles.active' argument. On command line use commas to separate multiple profiles.
Name |
|
|---|---|
Type |
|
Default value |
|
User property |
|
Since |
|
skip
Skip the execution.
Name |
|
|---|---|
Type |
|
Default value |
|
User property |
|
Since |
|
systemPropertyVariables
List of JVM system properties to pass to the process. NOTE: a forked process is required to use this feature.
Name |
|
|---|---|
Type |
|
Default value |
|
User property |
|
Since |
|
useTestClasspath
Flag to include the test classpath when running.
Name |
|
|---|---|
Type |
|
Default value |
|
User property |
|
Since |
|
workingDirectory
Current working directory to use for the application. If not specified, basedir will be used. NOTE: a forked process is required to use this feature.
Name |
|
|---|---|
Type |
|
Default value |
|
User property |
|
Since |
|
5.2. Examples
5.2.1. Debug the Application
By default, the run goal runs your application in a forked process.
If you need to debug it, you should add the necessary JVM arguments to enable remote debugging.
The following configuration suspend the process until a debugger has joined on port 5005:
<project>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
<version>2.3.0.M1</version>
<configuration>
<jvmArguments>
-Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=y,address=5005
</jvmArguments>
</configuration>
</plugin>
</plugins>
</build>
</project>These arguments can be specified on the command line as well, make sure to wrap that properly, that is:
$ mvn spring-boot:run -Dspring-boot.run.jvmArguments="-Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=y,address=5005"
5.2.2. Using System Properties
System properties can be specified using the systemPropertyVariables attribute.
The following example sets property1 to test and property2 to 42:
<project>
<build>
<properties>
<my.value>42</my.value>
</properties>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
<version>2.3.0.M1</version>
<configuration>
<systemPropertyVariables>
<property1>test</property1>
<property2>${my.value}</property2>
</systemPropertyVariables>
</configuration>
</plugin>
</plugins>
</build>
</project>If the value is empty or not defined (i.e. <my-property/>), the system property is set with an empty String as the value.
Maven trims values specified in the pom so it is not possible to specify a System property which needs to start or end with a space via this mechanism: consider using jvmArguments instead.
Any String typed Maven variable can be passed as system properties.
Any attempt to pass any other Maven variable type (e.g. a List or a URL variable) will cause the variable expression to be passed literally (unevaluated).
The jvmArguments parameter takes precedence over system properties defined with the mechanism above.
In the following example, the value for property1 is overridden:
$ mvn spring-boot:run -Dspring-boot.run.jvmArguments="-Dproperty1=overridden"
5.2.3. Using Environment Variables
Environment variables can be specified using the environmentVariables attribute.
The following example sets the 'ENV1', 'ENV2', 'ENV3', 'ENV4' env variables:
<project>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
<version>2.3.0.M1</version>
<configuration>
<environmentVariables>
<ENV1>5000</ENV1>
<ENV2>Some Text</ENV2>
<ENV3/>
<ENV4></ENV4>
</environmentVariables>
</configuration>
</plugin>
</plugins>
</build>
</project>If the value is empty or not defined (i.e. <MY_ENV/>), the env variable is set with an empty String as the value.
Maven trims values specified in the pom so it is not possible to specify an env variable which needs to start or end with a space.
Any String typed Maven variable can be passed as system properties.
Any attempt to pass any other Maven variable type (e.g. a List or a URL variable) will cause the variable expression to be passed literally (unevaluated).
Environment variables defined this way take precedence over existing values.
5.2.4. Specify Active Profiles
The active profiles to use for a particular application can be specified using the profiles argument.
The following configuration enables the foo and bar profiles:
<project>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
<version>2.3.0.M1</version>
<configuration>
<profiles>
<profile>foo</profile>
<profile>bar</profile>
</profiles>
</configuration>
</plugin>
</plugins>
</build>
</project>The profiles to enable can be specified on the command line as well, make sure to separate them with a comma, as shown in the following example:
$ mvn spring-boot:run -Dspring-boot.run.profiles=foo,bar
6. Running Integration tests
While you may start your Spring Boot application very easily from your test (or test suite) itself, it may be desirable to handle that in the build itself.
To make sure that the lifecycle of your Spring Boot application is properly managed around your integration tests, you can use the start and stop goals, as shown in the following example:
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
<version>2.3.0.M1</version>
<executions>
<execution>
<id>pre-integration-test</id>
<goals>
<goal>start</goal>
</goals>
</execution>
<execution>
<id>post-integration-test</id>
<goals>
<goal>stop</goal>
</goals>
</execution>
</executions>
</plugin>
</plugins>
</build>Such setup can now use the failsafe-plugin to run your integration tests as you would expect.
You could also configure a more advanced setup to skip the integration tests when a specific property has been set, see the dedicated example.
6.1. spring-boot:start
org.springframework.boot:spring-boot-maven-plugin:2.3.0.M1
Start a spring application. Contrary to the run goal, this does not block and allows other goals to operate on the application. This goal is typically used in integration test scenario where the application is started before a test suite and stopped after.
6.1.1. Required parameters
| Name | Type | Default |
|---|---|---|
|
|
6.1.2. Optional parameters
| Name | Type | Default |
|---|---|---|
|
|
|
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||
|
||
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||
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||
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||
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||
|
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|
||
|
||
|
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6.1.3. Parameter details
addResources
Add maven resources to the classpath directly, this allows live in-place editing of resources. Duplicate resources are removed from target/classes to prevent them to appear twice if ClassLoader.getResources() is called. Please consider adding spring-boot-devtools to your project instead as it provides this feature and many more.
Name |
|
|---|---|
Type |
|
Default value |
|
User property |
|
Since |
|
agents
Path to agent jars. NOTE: a forked process is required to use this feature.
Name |
|
|---|---|
Type |
|
Default value |
|
User property |
|
Since |
|
arguments
Arguments that should be passed to the application.
Name |
|
|---|---|
Type |
|
Default value |
|
User property |
|
Since |
|
classesDirectory
Directory containing the classes and resource files that should be packaged into the archive.
Name |
|
|---|---|
Type |
|
Default value |
|
User property |
|
Since |
|
environmentVariables
List of Environment variables that should be associated with the forked process used to run the application. NOTE: a forked process is required to use this feature.
Name |
|
|---|---|
Type |
|
Default value |
|
User property |
|
Since |
|
excludeGroupIds
Comma separated list of groupId names to exclude (exact match).
Name |
|
|---|---|
Type |
|
Default value |
|
User property |
|
Since |
|
excludes
Collection of artifact definitions to exclude. The Exclude element defines a groupId and artifactId mandatory properties and an optional classifier property.
Name |
|
|---|---|
Type |
|
Default value |
|
User property |
|
Since |
|
folders
Additional folders besides the classes directory that should be added to the classpath.
Name |
|
|---|---|
Type |
|
Default value |
|
User property |
|
Since |
|
fork
Flag to indicate if the run processes should be forked. Disabling forking will disable some features such as an agent, custom JVM arguments, devtools or specifying the working directory to use.
Name |
|
|---|---|
Type |
|
Default value |
|
User property |
|
Since |
|
includes
Collection of artifact definitions to include. The Include element defines a groupId and artifactId mandatory properties and an optional classifier property.
Name |
|
|---|---|
Type |
|
Default value |
|
User property |
|
Since |
|
jmxName
The JMX name of the automatically deployed MBean managing the lifecycle of the spring application.
Name |
|
|---|---|
Type |
|
Default value |
|
User property |
|
Since |
jmxPort
The port to use to expose the platform MBeanServer if the application is forked.
Name |
|
|---|---|
Type |
|
Default value |
|
User property |
|
Since |
jvmArguments
JVM arguments that should be associated with the forked process used to run the application. On command line, make sure to wrap multiple values between quotes. NOTE: a forked process is required to use this feature.
Name |
|
|---|---|
Type |
|
Default value |
|
User property |
|
Since |
|
mainClass
The name of the main class. If not specified the first compiled class found that contains a 'main' method will be used.
Name |
|
|---|---|
Type |
|
Default value |
|
User property |
|
Since |
|
maxAttempts
The maximum number of attempts to check if the spring application is ready. Combined with the "wait" argument, this gives a global timeout value (30 sec by default)
Name |
|
|---|---|
Type |
|
Default value |
|
User property |
|
Since |
noverify
Flag to say that the agent requires -noverify.
Name |
|
|---|---|
Type |
|
Default value |
|
User property |
|
Since |
|
profiles
The spring profiles to activate. Convenience shortcut of specifying the 'spring.profiles.active' argument. On command line use commas to separate multiple profiles.
Name |
|
|---|---|
Type |
|
Default value |
|
User property |
|
Since |
|
skip
Skip the execution.
Name |
|
|---|---|
Type |
|
Default value |
|
User property |
|
Since |
|
systemPropertyVariables
List of JVM system properties to pass to the process. NOTE: a forked process is required to use this feature.
Name |
|
|---|---|
Type |
|
Default value |
|
User property |
|
Since |
|
useTestClasspath
Flag to include the test classpath when running.
Name |
|
|---|---|
Type |
|
Default value |
|
User property |
|
Since |
|
wait
The number of milli-seconds to wait between each attempt to check if the spring application is ready.
Name |
|
|---|---|
Type |
|
Default value |
|
User property |
|
Since |
workingDirectory
Current working directory to use for the application. If not specified, basedir will be used. NOTE: a forked process is required to use this feature.
Name |
|
|---|---|
Type |
|
Default value |
|
User property |
|
Since |
|
6.2. spring-boot:stop
org.springframework.boot:spring-boot-maven-plugin:2.3.0.M1
Stop an application that has been started by the "start" goal. Typically invoked once a test suite has completed.
6.2.1. Optional parameters
| Name | Type | Default |
|---|---|---|
|
||
|
||
|
||
|
|
6.2.2. Parameter details
fork
Flag to indicate if process to stop was forked. By default, the value is inherited from the MavenProject. If it is set, it must match the value used to StartMojo start the process.
Name |
|
|---|---|
Type |
|
Default value |
|
User property |
|
Since |
|
jmxName
The JMX name of the automatically deployed MBean managing the lifecycle of the application.
Name |
|
|---|---|
Type |
|
Default value |
|
User property |
|
Since |
jmxPort
The port to use to lookup the platform MBeanServer if the application has been forked.
Name |
|
|---|---|
Type |
|
Default value |
|
User property |
|
Since |
skip
Skip the execution.
Name |
|
|---|---|
Type |
|
Default value |
|
User property |
|
Since |
|
6.3. Examples
6.3.1. Random Port for Integration Tests
One nice feature of the Spring Boot test integration is that it can allocate a free port for the web application.
When the start goal of the plugin is used, the Spring Boot application is started separately, making it difficult to pass the actual port to the integration test itself.
The example below showcases how you could achieve the same feature using the Build Helper Maven Plugin:
<project>
<build>
<plugins>
<plugin>
<groupId>org.codehaus.mojo</groupId>
<artifactId>build-helper-maven-plugin</artifactId>
<version>1.2.3</version>
<executions>
<execution>
<id>reserve-tomcat-port</id>
<goals>
<goal>reserve-network-port</goal>
</goals>
<phase>process-resources</phase>
<configuration>
<portNames>
<portName>tomcat.http.port</portName>
</portNames>
</configuration>
</execution>
</executions>
</plugin>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
<version>2.3.0.M1</version>
<executions>
<execution>
<id>pre-integration-test</id>
<goals>
<goal>start</goal>
</goals>
<configuration>
<arguments>
<argument>--server.port=${tomcat.http.port}</argument>
</arguments>
</configuration>
</execution>
<execution>
<id>post-integration-test</id>
<goals>
<goal>stop</goal>
</goals>
</execution>
</executions>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-failsafe-plugin</artifactId>
<version>1.2.3</version>
<configuration>
<systemPropertyVariables>
<test.server.port>${tomcat.http.port}</test.server.port>
</systemPropertyVariables>
</configuration>
</plugin>
</plugins>
</build>
</project>You can now retrieve the test.server.port system property in any of your integration test to create a proper URL to the server.
6.3.2. Skip Integration Tests
The skip property allows to skip the execution of the Spring Boot maven plugin altogether.
This example shows how you can skip integration tests with a command-line property and still make sure that the repackage goal runs:
<project>
<properties>
<skip.it>false</skip.it>
</properties>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
<version>2.3.0.M1</version>
<executions>
<execution>
<id>pre-integration-test</id>
<goals>
<goal>start</goal>
</goals>
<configuration>
<skip>${skip.it}</skip>
</configuration>
</execution>
<execution>
<id>post-integration-test</id>
<goals>
<goal>stop</goal>
</goals>
<configuration>
<skip>${skip.it}</skip>
</configuration>
</execution>
</executions>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-failsafe-plugin</artifactId>
<version>1.2.3</version>
<configuration>
<skip>${skip.it}</skip>
</configuration>
</plugin>
</plugins>
</build>
</project>By default, the integration tests will run but this setup allows you to easily disable them on the command-line as follows:
$ mvn verify -Dskip.it=true
7. Integrating with Actuator
Spring Boot Actuator displays build-related information if a META-INF/build-info.properties file is present.
The build-info goal generates such file with the coordinates of the project and the build time.
It also allows you to add an arbitrary number of additional properties, as shown in the following example:
<project>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
<version>2.3.0.M1</version>
<executions>
<execution>
<goals>
<goal>build-info</goal>
</goals>
<configuration>
<additionalProperties>
<encoding.source>UTF-8</encoding.source>
<encoding.reporting>UTF-8</encoding.reporting>
<java.source>${maven.compiler.source}</java.source>
<java.target>${maven.compiler.target}</java.target>
</additionalProperties>
</configuration>
</execution>
</executions>
</plugin>
</plugins>
</build>
</project>This configuration will generate a build-info.properties at the expected location with four additional keys.
Note that maven.compiler.source and maven.compiler.target are expected to be regular properties available in the project.
They will be interpolated as you would expect.
7.1. spring-boot:build-info
org.springframework.boot:spring-boot-maven-plugin:2.3.0.M1
Generate a build-info.properties file based the content of the current MavenProject.
7.1.1. Optional parameters
| Name | Type | Default |
|---|---|---|
|
||
|
|
|
|
7.1.2. Parameter details
additionalProperties
Additional properties to store in the build-info.properties. Each entry is prefixed by build. in the generated build-info.properties.
Name |
|
|---|---|
Type |
|
Default value |
|
User property |
|
Since |
outputFile
The location of the generated build-info.properties.
Name |
|
|---|---|
Type |
|
Default value |
|
User property |
|
Since |
time
The value used for the build.time property in a form suitable for Instant#parse(CharSequence). Defaults to session.request.startTime. To disable the build.time property entirely, use 'off'.
Name |
|
|---|---|
Type |
|
Default value |
|
User property |
|
Since |
|
8. Help information
The help goal is a standard goal that displays information on the capabilities of the plugin.
8.1. spring-boot:help
org.springframework.boot:spring-boot-maven-plugin:2.3.0.M1
Display help information on spring-boot-maven-plugin. Call mvn spring-boot:help -Ddetail=true -Dgoal=<goal-name> to display parameter details.
8.1.1. Optional parameters
| Name | Type | Default |
|---|---|---|
|
|
|
|
||
|
|
|
|
|
8.1.2. Parameter details
detail
If true, display all settable properties for each goal.
Name |
|
|---|---|
Type |
|
Default value |
|
User property |
|
Since |
goal
The name of the goal for which to show help. If unspecified, all goals will be displayed.
Name |
|
|---|---|
Type |
|
Default value |
|
User property |
|
Since |
indentSize
The number of spaces per indentation level, should be positive.
Name |
|
|---|---|
Type |
|
Default value |
|
User property |
|
Since |
lineLength
The maximum length of a display line, should be positive.
Name |
|
|---|---|
Type |
|
Default value |
|
User property |
|
Since |