How do I get started with Java development on a Mac running the MRJ?
Michael Dalrymple At a very minimum you'll need a decent text editor, BBEdit is one of the best, and the Mac OS Runtime for Java(MRJ) SDK. With this set of tools you will be able to edit your source code and compile it using the SDK. While there are more integrated development environments (IDE) for Windows, arguably one of the best is CodeWarrior which is also available for the Macintosh. Free training for CodeWarrior is available at CodeWarriorU. As you begin to develop more complex projects you'll want to make use of an IDE's source code management and debugging features.
There is a book called Learn Java on The Macintosh by Dave Mark but it is out of print. Once you figure out how to use the MRJ, any Java primer should work well.