BEA’s dev2dev has published a great article on thread dumps and tools for making the reading and parsing of them easier. For the uninitiated, thread dumps show the state of all threads at that point in time for any given process including a JVM. In UNIX, sending a process a -3 or -QUIT will generate the thread dump and send it out to system.out. On Windows, you can send a CTRL-BREAK in the DOS Window to generate the thread dump. Thread dumps are really helpful in debugging issues with your application, especially with deadlock issues.
In my blog entry entitled My Love Affair with JRockit, I showed how JRockit has the facility built into it to generate thread-dumps for any running JRockit VM.
In this dev2dev article, the author discusses the idea of taking the hard-to-read thread dumps and then converting them to XML to add some structure. Once the thread-dumps are converted to XML, you can apply a XSL stylesheet to format the XML document into something more readable and meaningful. In the article, the author converts a XML thread-dump into an HTML document and an image (700k). Great read and a great idea.