YourKit Java Profiler is a CPU and memory profiler that makes it easy to solve wide range of CPU- and memory-related performance problems. It features automatic leak detection, powerful tools for the analysis of memory distribution, an object heap browser, comprehensive memory tests as part of your JUnit testing process, extremely low profiling overhead, transparent deobfuscation support, and integration with Eclipse, JBuilder, IntelliJ IDEA, NetBeans, and JDeveloper IDEs.
Jmx4Perl provides an alternate way of accessing Java JEE Server management interfaces that are based on JMX (Java Management Extensions). It is an agent-based approach where a small Web application deployed on the application server provides HTTP/JSON-based access to JMX MBeans registered within the application server. It is set up from a handful of Perl modules, which can be integrated seamlessly in your own programs. It also includes a Nagios plugin, check_jmx4perl, a jmx4perl command line tool for remote JMX queries and operations, and a readline-based JMX shell j4psh, with context sensitive command completion and syntax highlighting.