title: Why debugging jdk libraries in eclipse, I can't see local variables values?
body: <p>The problem is that while debugging java library classes, e.g. HashSet functions I cant see local variables. On <code>variables</code> tab I can only see function parameters and <em>this</em>'s fields. When I'm trying to add local variable to <code>watch</code>, eclipse says: "errors during evaluation". </p>
  
  <p>So my question is why does this happens? And how can I see those local variables values?</p>