title: No source attachment in Java
body: <p>I am trying to use an external <code>.jar</code> file in my project. I have put that <code>.jar</code> file in my project's /lib folder, and I have referenced it in the build path. However, when I try to use it in code, I can't get the javadoc for it, nor I can see the actual code from the referenced classes. It says it <strong>has no source attachment</strong>. What is it meant by source attachment? I do have a javadoc folder that came with it, but when I attach it to my build path, it still reports it could not found the javadoc for the classes. Any ideas on that?</p>
  
  <p>I want to be able to see the javadoc.</p>