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There are lots of things you might expect to find in a book on this subject, but O'Reilly's Short Cut series has a standard format of "about fifty pages."
Open source Java developers have an amazing ability to turn out new tools. There are simply too many to list. I have found profiling tools to be particularly useful, and one profiler that I have used is JMP (http://www.khelekore.org/jmp), but it has many competitors. Another is JConsole, which ships with Java 5 and Java 6; JConsole does memory and thread profiling as well as JMX management, both locally and remotely.