Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Excellent, but quite advanced

As at least one previous reviewer has stressed, this is _not_ a book for beginners. It is also not necessarily a book for users who simply want access to algorithm code (although the code is excellent, easy to read, and fully Java-aware). However, for the advanced user, it does an excellent job of living up to its title, particularly in its analysis of various algorithms (as opposed to simply describing those algorithms and printing the code for them). It crams a lot of thought into 542 pages, but be prepared to take it all in slowly. This is no "Algorithms for Dummies" book, but it is the best book I have seen for algorithm development in Java, and one of the best I've seen that discusses algorithms in general.