Ask YS: Java Platform Book Recommendation?

We're moving some of our Windows-centric stuff to multi-platform environment. While "Java the Language" is something we're not interested in, "Java the Platform" looks promising, especially due to mature Rhino and Jython pieces. Which book would you recommend to learn "Java the Platform" quickly? Something less than 900 pages and without explanations of differences between local and global variables? We are looking into a Quick Intro into Java Platform for hackers. Thank you.