MonkeyWrench is a Swing-based Java profiling application.  It takes advantage of Java's management interface and instrumentation hooks, enabling you to:

• Collect CPU and wall-clock statistics at the class constructor and method level, for the classes you select, with detailed information on the stack trace signatures and threads involved with each constructor or method;

• Monitor object creation, also with associated stack trace signatures and associated threads;

• Monitor all threads in the target application, focusing on those with the most CPU time (either in a window or cumulative); also monitor thread contention and deadlocks, all sampled at the time interval of your choice.

• Graphically monitor the real-time behavior of the JVM garbage collectors, viewing both the number of collections, and the total time consumed collecting, also sampling at the time interval that you choose.

Resources

• Download
• README.txt
• Getting Started Guide
• Dzone/JavaLobby Article: Java Profiling with MonkeyWrench

MonkeyWrench uses well-defined Java APIs, and its Swing interface makes it easy to begin profiling an application.  It can be launched at target launch time, or, for HotSpot JVMs, a MonkeyWrench launcher application can be used to locate and attach to already-running JVMs. 

MonkeyWrench provides in one place information you'd normally need to collect from multiple applications (e.g., method CPU times, hprof-style site summaries, and thread-contention monitoring).  Finally, since the source is available, you can customize it to provide just what you want, and only what you want, for your needs.