JVM command-line tools can be used to provide valuable information about hung Java processes or Java core dumps. These tools include the following:
jstack: Prints Java stack traces of Java threads for a given Java process or core file or a remote debug server.
jinfo: Prints Java configuration information for a given Java process or core file or a remote debug server.
jmap: Prints shared object memory maps or heap memory details for a given process or core file or a remote debug server.
jsadebugd: Attaches to a Java process or core file and acts as a debug server. Remote clients such as jstack, jmap, and jinfo can attach to the server using Java Remote Invocation Method (RMI).
jhat: Enables Java heap dumps to be browsed using a web browser.
jstat: Displays performance statistics for an instrumented HotSpot JVM.
jps: Lists the instrumented HotSpot JVMs on the target system