Maven

Add the M2_HOME environment variable and M2 to  %M2_HOME%\bin, path to include %M2%
mvn --version
mvn archetype:generate -DgroupId=com.mycompany.app -DartifactId=my-app -DarchetypeArtifactId=maven-archetype-quickstart -DinteractiveMode=false
mvn package
java -cp target/my-app-1.0-SNAPSHOT.jar com.mycompany.app.App
A POM requires that its groupId, artifactId, and version be configured. These three values form the project's fully qualified artifact name. This is in the form of <groupId>:<artifactId>:<version>.
If you are using Eclipse IDE, just call:

mvn eclipse:eclipse

or from Eclipse, import existing Maven Projects

The standard for a Maven repository is to store an artifact in the following directory relative to the root of the repository:
/<groupId>/<artifactId>/<version>/<artifactId>-<version>.<packaging>

Maven will run with sensible defaults, so you can get right into it. However, if you are operating under a restricted environment or behind a firewall, you might need to prepare to run Maven, as it requires write access to the home directory (~/.m2 on Unix/Mac OS X and C:\Documents and Settings\username\.m2 on Windows) and network access to download binary dependencies.

The location of your local repository can be changed in your user configuration (M2_HOME/conf/settings.xml). The default value is ${user.home}/.m2/repository/.

<settings>
  ...
  <localRepository>/path/to/local/repo/</localRepository>
  ...
</settings>

Note: The local repository must be an absolute path.

Use 

mvn install
to install the artifact (the JAR file) you've generated into your local repository. 
Use
mvn eclipse:eclipse
to generate an Eclipse descriptor
Use mvn help:effective-pom
(mvn help:effective-pom -Doutput=wpom.xml)
see a much larger POM which exposes the default settings of Maven for debug.
Use mvn dependency:resolve

mvn dependency:tree

to find out what is on the classpath

mvn exec:java -Dexec.mainClass=org.sonatype.mavenbook.weather.Main \
      -Dexec.args="70112"

For a full description of the Exec plugin, run:

$ mvn help:describe -Dplugin=exec -Dfull

A test-scoped dependency is a dependency that is available on the classpath only during test compilation and test execution.

        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-io</artifactId>
            <version>1.3.2</version>
            <scope>test</scope>
        </dependency>




resources:resources

plugin is bound to the process-resources phase. This goal copies all of the resources from src/main/resources and any other configured resource directories to the output directory.

surefire:test

bound to the test phase. This goal executes all of the tests and creates output files that capture detailed results. By default, this goal will terminate a build if there is a test failure.