Java Tools Tutorials - Herong's Tutorial Examples - v6.21, by Dr. Herong Yang
jhat - Starting Web Server on a Heap Dump File
This section provides a tutorial example on how to start 'jhat' as a Web server on a Java heap dump file allowing you to browse Java heap objects.
Warning: "jhat" has been discontinued since JDK 9. But if you still have JDK 1.8 installed, you can continue to use it to browser heap dump files generated by JDK 9 to JDK 12.
In an earlier tutorial example, I created a Java heap dump file with the "jmap" tool on my GarbageCollection.java program. The heap dump file is named as GarbageCollection.map. Now I want to try to run the "jhat" Web server on this dump file and browse the heap dump with a Web browser.
1. Run the "jhat" command with default options:
herong> \Progra~1\java\jdk1.8.0\bin\jhat GarbageCollection.map Reading from GarbageCollection.map... Dump file created Jan 1 00:08:10 EDT 2008 Snapshot read, resolving... Resolving 67324 objects... Chasing references, expect 13 dots............. Eliminating duplicate references............. Snapshot resolved. Started HTTP server on port 7000 Server is ready.
2. Run a Web browser with http://localhost:7000. The heap dump first page shows up.
See next sections on how to use "jhat" Web server to browse heap objects.
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