title: maven: multi-module project assembly into single jar
body: <p>I have a multi-module project and want to create a single jar containing the classes of all my modules. Inside my parent POM, I declared the following plugin:</p>
  
  <pre><code>&lt;plugin&gt;
   &lt;groupId&gt;org.apache.maven.plugins&lt;/groupId&gt;
   &lt;artifactId&gt;maven-assembly-plugin&lt;/artifactId&gt;
   &lt;configuration&gt;
    &lt;descriptorRefs&gt;
     &lt;descriptorRef&gt;bin&lt;/descriptorRef&gt;
    &lt;/descriptorRefs&gt;
   &lt;/configuration&gt;
  &lt;/plugin&gt;
  </code></pre>
  
  <p>However, when running mvn assembly:assembly, only the source from the parent folder (empty) are included. How do I include the sources from my modules into the archive?</p>