Maven cheat sheet

I’ve put together some Maven commands, properties and command line options.

Creating a project packed as jar:

mvn archetype:generate \
    -DgroupId=com.example.project \
    -DartifactId=application

Creating a project packed as war:

mvn archetype:generate \
    -DgroupId=com.example.project \
    -DartifactId=application \
    -DarchetypeArtifactId=maven-archetype-webapp

Setting the source code encoding:

<properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
</properties>

Setting the Java version:

<properties>
    <maven.compiler.source>1.8</maven.compiler.source>
    <maven.compiler.target>1.8</maven.compiler.target>
</properties>

Default lifecycle #

The default lifecycle consist of the following phases:

Phase	Description
`validate`	Validate the project, checking if everything is correct.
`compile`	Compile source code of the project and store classes in `target/classes`.
`test`	Run the tests.
`package`	Take the compiled code and package it in its distributable format, sucg as JAR or WAR.
`verify`	Run any checks to verify the package is valid and meets quality criteria.
`install`	Install the package into the local repository, or use as a dependency in other projects locally.
`deploy`	Copies the final package to the remote repository.

Use mvn <phase name> to execute a phase.

Command line option	Description
`-DskipTests`	Compile the tests but don’t run them
`-Dmaven.test.skip=true`	Don’t compile the tests and don’t run them
`-X` or `--debug`	Enable debug output
`-U` or `--update-snapshots`	Forces a check for updated releases and snapshots on remote repositories
`-o` or `--offline`	Work offline (run as if no network connection is available)
`-l <file path>` or `--log-file <file path>`	Writes the build output to a file
`-v` or `--version`	Display Maven version

Property	Description
`${project.groupId}`	Project’s group id
`${project.artifactId}`	Project’s artifact id
`${project.version}`	Project’s version
`${project.name}`	Project’s name
`${project.description}`	Project’s description
`${project.basedir}`	Directory containing the `pom.xml` file
`${project.baseUri}`	Directory containing the `pom.xml` file as URI
`${project.build.sourceDirectory}`	Project source directory
`${project.build.testSourceDirectory}`	Project test source directory
`${project.build.outputDirectory}`	Project output directory
`${project.build.testOutputDirectory}`	Project test output directory
`${project.build.directory}`	Directory which contains all of these output directories (`target`)
`${project.build.finalName}`	Final name of the file created when the built project is packaged

Property	Description
`${maven.build.timestamp}`	The UTC timestamp of build start, in `yyyy-MM-dd'T'HH:mm:ss'Z'` default format
`${build.timestamp}`	Same as `${maven.build.timestamp}`
`${maven.build.timestamp.format}`	Can be used to override the default format for the build timestamp

Property	Description
`${java.class.path}`	Java class path
`${java.home}`	Java installation directory
`${java.vendor}`	Java Runtime Environment vendor
`${java.version}`	Java Runtime Environment version
`${line.separator}`	Line separator
`${file.separator}`	File separator
`${os.name}`	Operating system name
`${os.arch}`	Operating system architecture
`${os.version}`	Operating system version
`${user.name}`	User’s account name
`${user.dir}`	User’s current working directory
`${user.home}`	User’s home directory

Dependency plugin: Provides the capability to manipulate artifacts.
- mvn dependency:tree: Show the dependency tree.
- mvn dependency:resolve: Resolve dependencies.
- mvn dependency:resolve-plugins: Resolve plugins.
Versions plugin: Manage the versions of artifacts in a project’s POM.
- mvn versions:set -DgenerateBackupPoms=false -DnewVersion=[new version]: Set a new project version.
Assembly plugin: Aggregate the project output along with its dependencies, modules and other files into a single distributable archive.
Release plugin: Plugin used to release a project.
Shade plugin: Package the artifact in an uber-jar, including its dependencies.
Javadoc plugin: Generate javadocs for a project.
- mvn javadoc:javadoc: Output javadocs HTML files in target/site/apidocs.