Monitoring Spring Application

Hello group:

I am looking for a monitoring Java application tool with spring 3.0 (not necessarily a Web app). It is important to measure performance, resources (cpu, memory), threads, etc. and send notifications if necessary.

I found the following libraries to measure performance:
http://jetm.void.fm/
http://jamonapi.sourceforge.net/
http://perf4j.codehaus.org/
http://beet.sourceforge.net/

And others for performance and something else:
http://code.google.com/p/xebia-france/
http://code.google.com/p/javasimon/ (I cannot use It With spring).
http://java-monitor.com/

To notify in case of exceptions i found (and I liked. It is simple and works with spring):
http://jalarms.sourceforge.net/

However, I would like your opinion or recommend me a monitoring tool for integrate with Spring.

Thank you very much.

Here are a few I've looked at depending what you need:
- JavaMelody (open source - http://code.google.com/p/javamelody/)
- PSI Probe (open source - http://code.google.com/p/psi-probe/)
- App Dynamics (expensive - http://www.appdynamics.com/)