title: Java: How to add JDK classes (e.g. javax.*) into custom JavaDoc indexes?
body: <p>I am creating an aggregated Javadoc for a big project.
  It's a Maven project and I am using Maven Javadoc plugin 2.8.1.</p>
  
  <p>I'd like to have javax.* classes in the indexes (i.e. left frames and the "all classes" index).
  But even if I add these to @packages, they are only linked, not included.</p>
  
  <p><strong>Is there a way to include JDK classes in the generaged Javadoc?</strong></p>