title: Eclipse Cannot create in-place editor
body: <p>I have a troubleshoot problem. My eclipse don't want open class in the package editor.</p>
  
  <p>Error, what i'm having - <img src="https://i.stack.imgur.com/6rGp6.png" alt="enter image description here"></p>
  
  <p>However, file opened with Open with->Text Editor. 
  That's looks like a charm kinda. help please.</p>