The book ''Java Game Programming for Dummies'' does a decent job of introducing you to the syntax of Java in a game development context. It can be a fun way to learn the language. If you want to develop anything other than trivial Java games you will have to learn the language in more detail such as the above post suggests, but the Dummies book may be an interesting way to start.
I must say that if you know a little of what you''re doing but don''t know how a game differs from an email program, Java Game Programming for Dummies can point you in the right direction. It shows you the basic basics of game loops, sprites, sprite engines, 3D, and scripting.
hmmmmmm what can I say about java, clean, moderately straight forward language, JDK provided by sun has excellent documentation. you shouldn''t have that much trouble making a transition to java, if you worked purely with classes and object in C++, it will be almost the same.