Below are other configuration examples for the help:describe goal.
The plugin parameter is meant to provide two things: convenience and prefix-based access.
The convenience comes when specifying a plugin by groupId:artifactId, or by groupId:artifactId:version. Where the more traditional specification of separate fields would mean specifying this:
# mvn help:describe -DgroupId=org.somewhere -DartifactId=some-plugin -Dversion=0.0.0
the use of the plugin parameter allows this:
# mvn help:describe -Dplugin=org.somewhere:some-plugin:0.0.0
Here is an example to describe the Help plugin:
# mvn help:describe -Dplugin=org.apache.maven.plugins:maven-help-plugin
Note: version is always optional here.
On the other hand, the plugin parameter also offers the option to specify a plugin by its prefix, like this:
# mvn help:describe -Dplugin=help
You can use the mojo parameter of the describe goal to show or display relative information about a particular goal of the plugin you specified.
For example, when you execute the following command:
# mvn help:describe -Dmojo=describe -DgroupId=org.apache.maven.plugins -DartifactId=maven-help-plugin
This would display brief information about the describe goal only.
You could also ask for a single Maven command, i.e. a goal or a phase or a lifecycle. It is the command when you call Maven, i.e.:
# mvn -help usage: mvn [options] [<goal(s)>] [<phase(s)>] ...
The following are some examples:
# mvn help:describe -Dcmd=clean ... [INFO] [help:describe] [INFO] 'clean' is a lifecycle with the following phases: * pre-clean: NOT DEFINED * clean: org.apache.maven.plugins:maven-clean-plugin:clean * post-clean: NOT DEFINED ...
# mvn help:describe -Dcmd=compile ... [INFO] [help:describe] [INFO] 'compile' is a phase corresponding to this plugin: org.apache.maven.plugins:maven-compiler-plugin:compile It is a part of the lifecycle for the POM packaging 'jar'. This lifecycle includes the following phases: * validate: NOT DEFINED * initialize: NOT DEFINED * generate-sources: NOT DEFINED * process-sources: NOT DEFINED * generate-resources: NOT DEFINED * process-resources: org.apache.maven.plugins:maven-resources-plugin:resources * compile: org.apache.maven.plugins:maven-compiler-plugin:compile * process-classes: NOT DEFINED * generate-test-sources: NOT DEFINED * process-test-sources: NOT DEFINED * generate-test-resources: NOT DEFINED * process-test-resources: org.apache.maven.plugins:maven-resources-plugin:testResources * test-compile: org.apache.maven.plugins:maven-compiler-plugin:testCompile * process-test-classes: NOT DEFINED * test: org.apache.maven.plugins:maven-surefire-plugin:test * package: org.apache.maven.plugins:maven-jar-plugin:jar * pre-integration-test: NOT DEFINED * integration-test: NOT DEFINED * post-integration-test: NOT DEFINED * verify: NOT DEFINED * install: org.apache.maven.plugins:maven-install-plugin:install * deploy: org.apache.maven.plugins:maven-deploy-plugin:deploy ...
# mvn help:describe -Dcmd=compiler:compile ... [INFO] 'compiler:compile' is a plugin goal (aka mojo). Mojo: 'compiler:compile' compiler:compile Description: Compiles application sources Deprecated. No reason given For more information, run 'mvn help:describe [...] -Ddetail' ...
If you want to display less or more detailed information, you can use the minimal, medium or full parameters.
The minimal parameter adds a minimal list of information:
# mvn help:describe -Dplugin=help -Dminimal=true ... [INFO] [help:describe] [INFO] org.apache.maven.plugins:maven-help-plugin:2.1-SNAPSHOT Group Id: org.apache.maven.plugins Artifact Id: maven-help-plugin Version: 2.1-SNAPSHOT Goal Prefix: help Description: The Maven Help plugin provides goals aimed at helping to make sense out of the build environment. It includes the ability to view the effective POM and settings files, after inheritance and active profiles have been applied, as well as a describe a particular plugin goal to give usage information. For more information, run 'mvn help:describe [...] -Ddetail' ...
The medium parameter is the default since 2.1 and adds a list with the mojos of the plugin and their descriptions:
# mvn help:describe -Dplugin=help
...
[INFO] org.apache.maven.plugins:maven-help-plugin:2.1-SNAPSHOT
Group Id: org.apache.maven.plugins
Artifact Id: maven-help-plugin
Version: 2.1-SNAPSHOT
Goal Prefix: help
Description: The Maven Help plugin provides goals aimed at helping to make
sense out of the build environment. It includes the ability to view the
effective POM and settings files, after inheritance and active profiles have
been applied, as well as a describe a particular plugin goal to give usage
information.
This plugin has 9 goals:
help:active-profiles
Description: Displays a list of the profiles which are currently active for
this build.
Deprecated. No reason given
help:all-profiles
Description: Displays a list of available profiles under the current
project.
Note: it will list all profiles for a project. If a profile comes up with a
status inactive then there might be a need to set profile activation
switches/property.
Deprecated. No reason given
help:describe
Description: Displays a list of the attributes for a Maven Plugin and/or
Mojo (Maven plain Old Java Object).
Deprecated. No reason given
help:effective-pom
Description: Displays the effective POM as an XML for this build, with the
active profiles factored in.
Deprecated. No reason given
help:effective-settings
Description: Displays the calculated settings as XML for this project,
given any profile enhancement and the inheritance of the global settings
into the user-level settings.
Deprecated. No reason given
help:evaluate
Description: Evaluates Maven expressions given by the user in an
interactive mode.
Deprecated. No reason given
help:expressions
Description: Displays the supported Plugin expressions used by Maven.
Deprecated. No reason given
help:help
Description: Display help information on maven-help-plugin.
Call
mvn help:help -Ddetail=true -Dgoal=<goal-name>
to display parameter details.
Deprecated. No reason given
help:system
Description: Displays a list of the platform details like system properties
and environment variables.
Deprecated. No reason given
For more information, run 'mvn help:describe [...] -Ddetail'
...
The full parameter also displays information about the mojos's implementation, their parameters and component requirements, among others.
# mvn help:describe -Dplugin=help -Dfull=true
Note: The medium parameter was added in version 2.0.2 and the minimal parameter was added in version 2.1 of this Help plugin.