Re: [Jython-users] Jython debugger?

[Kevin B. <kb...@ca...>]

Edward Povazan wrote:
> 
> Hello,
> 
> Is there a jython debugger in existence? 

The python debugger (pdb module) works well for Jython.  See http://www.python.org/doc/current/lib/module-pdb.html

However, it does lack cross-language debugging capability (i.e., you can't step into Java methods).

> If not, has anyone ever
> contemplated what would be necessary to implement one?

I imagine anyone who uses Jython extensively has contemplated it, :-)  but I don't think anyone has developed one yet (though I would _love_ to be proven wrong on that!)

It would probably need to be out-of-process (or it couldn't be written in java/jython...), and use the Java Platform Debugger Architecture interfaces  (http://java.sun.com/j2se/1.3/docs/guide/jpda/), especially the Wire Protocol to control the VM-to-be-debugged, and then use the Python Debugger to control the Jython interpreter within the VM.  

It may be best to enhance an existing Java debugger with knowledge about controlling pdb (or the features pdb is built on - bdb & sys.settrace() )

Candidates for extension include:
	JSwat - GPL & appears flexible: http://www.bluemarsh.com/java/jswat/ 
	NetBeans IDE - MPL-like & appears big: http://www.netbeans.org/)

So yeah, I've contemplated it, too.  :-)

kb