Many of these books are among "the classics" for Java, JEE, Spring & Hibernate development. 

Java Persistence With Hibernate, by C. Bauer & G King, Manning Press, 2007

Pro Java EE Spring Patterns, by D. Kayal, Apress, 2008

The Spring Framework - Reference Documentation, v2.5 , by SpringSource, 2008

High Performance Web Sites, By S. Souders, O'Reilly Media, 2007

Pro Spring 2.5, by J. Machacek et. al, Apress, 2008

MySQL (Fourth Edition), by P. DuBois, Addison Wesley, 2009

Pro CSS and HTML Design Patterns, By M. Bowers, Apress, 2007

These other books have been essential while building up my tool chest with Spring, Hibernate and other technologies:

Spring Recipes, by G Mak, Apress, 2008

Spring Persistence - A Running Start, by P. T. Fisher & S. Duskis, Apress, 2009

Harnessing HIbernate, by J Elliott & T. O'Brien & R. Fowler, O'Reilly Media, 2008