Depending on where he is in terms of learning programing, Processing might be a good entry point. It's actually an IDE, preprocessor and a Java library put together; it obscures some of the more complicated bits of Java syntax and focuses on visual, animated, interactive programs. It's got a pretty robust corpus of documentation, books, and examples. posted by lantius at 11:09 PM on December 4, 2011 [1 favorite]
iTunesU has a great Java programming class by Stanford for free. I think it's called "Programming Methodologies". posted by lohmannn at 8:41 AM on December 5, 2011
There are some relevant questions on stackoverflow too.
posted by jeffburdges at 9:38 PM on December 4, 2011