Useful Maven commandos

Everybody who uses Maven from console / terminal knows how sometimes difficult to remember all handy commandos using in day job. A small reference list should help.

Skip running tests for a particular project.

mvn clean install -Dmaven.test.skip=true

Continue build if it has been failed at certain point. Maybe you have many sub-projects and build your entire project from top to down. "-rf" parameters allow to continue maven running where you want after any build errors. Assume my current top directory where I let Maven run is D:\SVN and the build was broken at D:\SVN\eIP\CoreServer\DatastoreConnector. Following command let go on with the build and skip this not compilable or not testable sub-project.

mvn clean install -rf eIP\CoreServer\DatastoreConnector

Get source jar files (e.g. for Eclipse projects). Having source files in local repository allow to jump into this directly from your preferred IDE.

mvn eclipse:eclipse -DdownloadSources=true

or run

mvn dependency:sources

to download all source jars for a given project into local repository. The same for JavaDoc (if it's available).

mvn eclipse:eclipse -DdownloadJavadocs=true

Output project's dependency tree. I like that! You can see versions of all used artefacts.

mvn dependency:tree

Output is like this one

[INFO] ip.client:ip-jsftoolkit:jar:3.4.1-SNAPSHOT
[INFO] +- ip.client:ip-filter-security:jar:3.4.0:compile
[INFO] |  +- com.scalaris.commons:scalaris-commons-enterprise:jar:2.3.1-SNAPSHOT:compile
[INFO] |  |  +- com.scalaris.commons:scalaris-commons-lang:jar:2.3.0:compile
[INFO] |  |  +- org.apache.commons:commons-lang3:jar:3.0:compile
[INFO] |  |  \- commons-lang:commons-lang:jar:2.6:compile
[INFO] |  +- ip.client:ip-client-commons:jar:3.4.0:compile
[INFO] |  |  +- ip.services:ip-core-services:jar:3.4.0:compile
[INFO] |  |  |  \- ip.datatransfer:ip-datatransfer-commons:jar:3.4.0:compile
..................................................
[INFO] |  +- commons-httpclient:commons-httpclient:jar:3.0.1:compile
[INFO] |  +- org.apache.commons:commons-jexl:jar:2.0:compile
[INFO] |  \- joda-time:joda-time:jar:1.6.2:compile
[INFO] +- javax.ejb:ejb:jar:3.0:provided
[INFO] +- javax.servlet:servlet-api:jar:2.5:provided
[INFO] \- com.scalaris.commons:scalaris-commons-test:jar:2.2.8-SNAPSHOT:test
[INFO]    +- jmock:jmock:jar:1.2.0:test
[INFO]    +- junit:junit:jar:3.8.2:test

Filter project's dependency tree in order to see only a specified dependency. The syntax for filter patterns is as follows: [groupId]:[artifactId]:[type]:[version]

mvn dependency:tree -Dincludes=com.sun.faces:jsf-impl

Display the effective pom of a project. The effective pom represents the current pom state for a project (incl. maven super pom and active profiles).

mvn help:effective-pom

Generate files needed for an IntelliJ IDEA project setup.

mvn idea:idea

This plugin has no way to determine the name of the JDK you are using. It uses by default the same JDK as output java -version. Using with defined JDK:

mvn idea:idea -DjdkName=1.5

Create a web project from scratch.

mvn archetype:create 
 -DarchetypeGroupId=org.apache.maven.archetypes 
 -DarchetypeArtifactId=maven-archetype-webapp 
 -DarchetypeVersion=1.0 
 -DgroupId=com.maventest 
 -DartifactId=mywebtest 
 -Dversion=1.0-SNAPSHOT

Deploy artefact in global repository (located e.g. in file://///xyz.abc.com/maven/repo-m2).

mvn deploy:deploy-file
 -DgroupId=com.maventest
 -DartifactId=mywebtest
 -Dversion=1.0-SNAPSHOT
 -Dpackaging=war
 -Dfile=mywebapp.jar
 -DrepositoryId=xyz-release 
 -Durl=file://///xyz.abc.com/maven/repo-m2

Check all the dependencies used in your project and display a list of those dependencies with newer versions available.

mvn versions:display-dependency-updates

...
[INFO] The following dependency updates are available:
[INFO]   org.apache.maven:maven-artifact ........................ 2.0 -> 2.0.9
[INFO]   org.apache.maven:maven-plugin-api ...................... 2.0 -> 2.0.9
[INFO]   org.apache.maven:maven-project ....................... 2.0.2 -> 2.0.9
[INFO]   org.codehaus.plexus:plexus-utils ....................... 1.1 -> 1.5.6

Check all the plugins and reports used in your project and display a list of those plugins with newer versions available.

mvn versions:display-plugin-updates

...
[INFO] The following plugin updates are available:
[INFO]   maven-deploy-plugin ...................................... 2.5 -> 2.7
[INFO]   maven-jar-plugin ..................................... 2.3.1 -> 2.3.2
[INFO]   maven-plugin-plugin ...................................... 2.7 -> 2.9
[INFO]   maven-resources-plugin ................................. 2.4.3 -> 2.5

Decompile Java classes in the maven central repository :-). Useful if source code isn't available. The trick is here.