Monitoring Tomcat JVM

[wa...@technologist.com]

Hi all!,

I'm looking for a way to monitor some parameters in the Tomcat JVM.

I just wonder if is there any tool for what I'm going to propose. Or, 
anyone 
that point me in the classes to modify and recompile (from the tomcat core) 
in order to somehow monitor tomcat (by System.out or writting to a file
or whatever). The main parameters I'm looking for are:

- To know how many httpSessions objects are instantiated in Tomcat at a 
particular time:
  I guest that anywhere in the tomcat code should be a 
Vector/Hasttable/array whith 
  the HttpSessions created. It could to be nice to have access these 
objects so I can 
  monitor how many are and access there Attribute list.

- To know how many servlets objects are in memory.

By now, I think that accesing these objects could solve many of my 
problems. 
Any ideas?

This is only for running a "custom" Tomcat server in order to
optimize the application I'm developing. I think my development team has 
left many "trash" in the code, so the system is keeping unused objects in
memory causing Tomcat to catch more and more RAM without releasing it
when the sessions get invalidated.

Thanks to all.

Bob.