COMPAS J2EE is a non-intrusive performance instrumentation and monitoring toolkit for J2EE.
It uses adaptive monitoring to automatically adjust the target coverage. COMPAS is completely portable across J2EE application servers and OSs.
Swing Spy is java based Swing/AWT spy agent that prints the widget under the cursor (like Spy++ for Windows/MFC and SWT Spy for Java-SWT). Download from the homepage: http://www.nenoff.com/swingspy/