title: maven assembly include all sub-module dependencies without "already added, skipping"
body: <p>So I have a parent module with a bunch of sub-modules, and I'm trying to generate a zip file with all of the module jars and all of their dependencies. My assembly descriptor looks like (similar to <a href="https://stackoverflow.com/questions/3436359/maven-assembly-plugin-include-dependencies-from-sub-modules">this question</a>):</p>
  
  <pre><code>&lt;assembly
      xmlns="http://maven.apache.org/plugins/maven-assembly-plugin/assembly/1.1.2"
      xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
      xsi:schemaLocation="http://maven.apache.org/plugins/maven-assembly-plugin/assembly/1.1.2 http://maven.apache.org/xsd/assembly-1.1.2.xsd"&gt;
      &lt;id&gt;bin&lt;/id&gt;
      &lt;formats&gt;
          &lt;format&gt;zip&lt;/format&gt;
      &lt;/formats&gt;
      &lt;moduleSets&gt;
          &lt;moduleSet&gt;
              &lt;useAllReactorProjects&gt;true&lt;/useAllReactorProjects&gt;
              &lt;binaries&gt;
                  &lt;outputDirectory&gt;/&lt;/outputDirectory&gt;
                  &lt;unpack&gt;false&lt;/unpack&gt;
                  &lt;dependencySets&gt;
                      &lt;dependencySet&gt;
                          &lt;outputDirectory&gt;lib&lt;/outputDirectory&gt;
                          &lt;unpack&gt;false&lt;/unpack&gt;
                          &lt;scope&gt;runtime&lt;/scope&gt;
                      &lt;/dependencySet&gt;
                  &lt;/dependencySets&gt;
              &lt;/binaries&gt;
          &lt;/moduleSet&gt;
      &lt;/moduleSets&gt;
  &lt;/assembly&gt;
  </code></pre>
  
  <p>Now in both maven 2 and maven 3 I'm seeing hundreds of messages that look like:</p>
  
  <pre><code>[INFO] distribution-0.5.1-SNAPSHOT/lib/commons-lang-2.4.jar already added, skipping
  [INFO] distribution-0.5.1-SNAPSHOT/lib/spring-core-3.0.3.RELEASE.jar already added, skipping
  [INFO] distribution-0.5.1-SNAPSHOT/lib/commons-logging-1.0.4.jar already added, skipping
  [INFO] distribution-0.5.1-SNAPSHOT/lib/args4j-2.0.12.jar already added, skipping
  [INFO] distribution-0.5.1-SNAPSHOT/lib/collections-generic-4.01.jar already added, skipping
  </code></pre>
  
  <p>I gather these are happening because many of my sub-modules share dependencies (and some sub-modules depend on other sub-modules) and maven is copying all transitive dependencies for each sub-module independently so there's a ton of repetition in there.</p>
  
  <p>Is there a way I can keep maven from trying to copy the same dependencies multiple times? Or at least hide these "already added, skipping" messages when it tries to?</p>