VisualVM: One of the best kept secrets
You update your JDK frequently to get the latest and greatest...but did you know about VisualVM. It may be one of the best kept secrets in the JDK. But now you know too!
The VisualVM application gives you visual insight into your application's use of resources: heap, threads, memory, CPU usage, and more. This is a profiling tool that you might consider paying for, but you won't -- it's free, and its right under your nose.
Check out The Best Kept Secret in the JDK: VisualVM for more information about this great tool.
If you go to JavaOne, make sure you attend Geertjan Wielenga's session too:
TS-4247, Getting More Out of the Java