title: Maven shade plugin overlapping classes vs. dependency plugin omitted for conflict
body: <p>I'm using the Maven shade plugin, and I get output like the following from <code>mvn package</code>:</p>
  
  <pre><code>[WARNING] kryo-4.0.0.jar, kryo-2.21.jar define 91 overlapping classes:
  </code></pre>
  
  <p>followed by:</p>
  
  <pre><code>[WARNING] maven-shade-plugin has detected that some class files are
  [WARNING] present in two or more JARs.
  [WARNING] single version of the class is copied to the uber jar.
  [WARNING] Usually this is not harmful and you can skip these warnings,
  [WARNING] otherwise try to manually exclude artifacts based on
  [WARNING] mvn dependency:tree -Ddetail=true and the above output.
  </code></pre>
  
  <p>On the other hand, there are many other jars that I would expect to get such warnings for, but I don't. In particular, if I do <code>mvn dependency:tree -Dverbose</code>, I get a lot of output like:</p>
  
  <pre><code>[INFO] |  |  +- (org.apache.commons:commons-lang3:jar:3.3.2:compile - omitted for conflict with 3.5)
  </code></pre>
  
  <p>My question is, why do some cases of duplicate classes result only in the "overlapping classes" warnings, while other cases result only in the "omitted for conflict" information messages?</p>