UPDATE 2022-02-14: This plugin has moved from coveooss to the spotify Github org. The new groupId will be com.spotify.fmt
, and the master
branch has been renamed to main
.
Formats your code using google-java-format which follows Google's code styleguide.
The format cannot be configured by design.
If you want your IDE to stick to the same format, google-java-format also includes integrations for IntelliJ and Eclipse IDE's, following the installation instructions on the README.
To have your sources automatically formatted on each build, add to your pom.xml:
<build>
<plugins>
<plugin>
<groupId>com.spotify.fmt</groupId>
<artifactId>fmt-maven-plugin</artifactId>
<version>VERSION</version>
<executions>
<execution>
<goals>
<goal>format</goal>
</goals>
</execution>
</executions>
</plugin>
</plugins>
</build>
If you prefer, you can only check formatting at build time using the check
goal:
<build>
<plugins>
<plugin>
<groupId>com.spotify.fmt</groupId>
<artifactId>fmt-maven-plugin</artifactId>
<version>VERSION</version>
<executions>
<execution>
<goals>
<goal>check</goal>
</goals>
</execution>
</executions>
</plugin>
</plugins>
</build>
Both goals have a Maven lifecycle phase configured by default.
Goal | Default Phase |
---|---|
format |
process-sources |
check |
verify |
You may prefer to run these goals in a different phase instead.
Maven allows you to override the default phase by specifying a <phase>
for the <execution>
.
For example, you may prefer that the check
goal is performed in an earlier phase such as validate
:
<execution>
<phase>validate</phase>
<goals>
<goal>check</goal>
</goals>
</execution>
sourceDirectory
represents the directory where your Java sources that need to be formatted are contained. It defaults to ${project.build.sourceDirectory}
testSourceDirectory
represents the directory where your test's Java sources that need to be formatted are contained. It defaults to ${project.build.testSourceDirectory}
additionalSourceDirectories
represents a list of additional directories that contains Java sources that need to be formatted. It defaults to an empty list.
verbose
is whether the plugin should print a line for every file that is being formatted. It defaults to false
.
filesNamePattern
represents the pattern that filters files to format. The defaults value is set to .*\.java
.
skip
is whether the plugin should skip the operation.
skipSortingImports
is whether the plugin should skip sorting imports.
skipSourceDirectory
is whether the plugin should skip formatting/checking the sourceDirectory
. It defaults to false
.
skipTestSourceDirectory
is whether the plugin should skip formatting/checking the testSourceDirectory
. It defaults to false
.
style
sets the formatter style to be google
or aosp
. By default this is google
. Projects using Android conventions may prefer aosp
.
forkMode
lets you specify whether to run google-java-format in a fork or in-process. Also adds JVM arguments to expose JDK internal javac APIs. Value default
(which is the default) will fork (to avoid warnings for JDK9+ and to be able to run at all for JDK16+), never
runs in-process, regardless of JDK version and always
will always fork.
example:
<build>
<plugins>
<plugin>
<groupId>com.spotify.fmt</groupId>
<artifactId>fmt-maven-plugin</artifactId>
<version>VERSION</version>
<configuration>
<sourceDirectory>some/source/directory</sourceDirectory>
<testSourceDirectory>some/test/directory</testSourceDirectory>
<verbose>true</verbose>
<filesNamePattern>.*\.java</filesNamePattern>
<additionalSourceDirectories>
<param>some/dir</param>
<param>some/other/dir</param>
</additionalSourceDirectories>
<skip>false</skip>
<skipSourceDirectory>false</skipSourceDirectory>
<skipTestSourceDirectory>false</skipTestSourceDirectory>
<skipSortingImports>false</skipSortingImports>
<style>google</style>
</configuration>
<executions>
<execution>
<goals>
<goal>format</goal>
</goals>
</execution>
</executions>
</plugin>
</plugins>
</build>
displayFiles
default = true. Display the list of the files that are not compliant.
displayLimit
default = 100. Number of files to display that are not compliant.
failOnError
default = true. Fail the build if non-compliant files are found.
example to not display the non-compliant files:
<build>
<plugins>
<plugin>
<groupId>com.spotify.fmt</groupId>
<artifactId>fmt-maven-plugin</artifactId>
<version>VERSION</version>
<configuration>
<displayFiles>false</displayFiles>
</configuration>
<executions>
<execution>
<goals>
<goal>check</goal>
</goals>
</execution>
</executions>
</plugin>
</plugins>
</build>
example to limit the display up to 10 files
<build>
<plugins>
<plugin>
<groupId>com.spotify.fmt</groupId>
<artifactId>fmt-maven-plugin</artifactId>
<version>VERSION</version>
<configuration>
<displayLimit>10</displayLimit>
</configuration>
<executions>
<execution>
<goals>
<goal>check</goal>
</goals>
</execution>
</executions>
</plugin>
</plugins>
</build>
example to only warn about non-compliant files instead of failing the build
<build>
<plugins>
<plugin>
<groupId>com.spotify.fmt</groupId>
<artifactId>fmt-maven-plugin</artifactId>
<version>VERSION</version>
<configuration>
<failOnError>false</failOnError>
</configuration>
<executions>
<execution>
<goals>
<goal>check</goal>
</goals>
</execution>
</executions>
</plugin>
</plugins>
</build>
You can also use it on the command line
mvn com.spotify.fmt:fmt-maven-plugin:format
You can pass parameters via standard -D
syntax.
mvn com.spotify.fmt:fmt-maven-plugin:format -Dverbose=true
-Dfmt.skip
is whether the plugin should skip the operation.
Starting from version 1.8, Google Java Formatter requires Java 11 to run. Incidently, all versions of this plugin starting from 2.10 inclusively also require this Java version to properly function. The 2.9.x release branch is the most up-to-date version that still runs on Java 8.
git checkout main && git pull
mvn release:prepare
- use x.y format for release version and x.y.z for SCM tag. (You can only do this as admin of the repo)mvn release:perform -P release
(make sure to use Maven settings which include credentials for the Sonatype staging repo)git fetch
- to make sure your local repo is up to date with the commits from the release plugin.- Create a GitHub release with merged PRs and other information.
- Check that the release is available in Sonatype staging
- Wait for the release to be available in Maven Central
- Update version used for actual formatting in the POM.