title: How to attach to a running jar and debug it?
body: <p>I have written an old app long time ago on another computer.
  This one does not exist anymore - and with it all the source is gone - but I still have the app in form of jar files.</p>
  
  <p>Now I need to check my old code what I have done in a particular place in code. I know I can create a java from it - but I need to check it while it's running...</p>
  
  <p>I have tried javasnoop - but it can not attach. It keeps trying but forever - other apps I can attach to and debug.</p>
  
  <p>is there any other way/tool that can attach to a running jar and debug it?</p>
  
  <p>If that makes a difference: the application is being started with an EXE file and then uses the jar libs...</p>
  
  <p>Thanks</p>