Here are some good books for an enterprise java developer (the order is not relevant). Please add your suggestions in the comments:

  • Patterns of Enterprise Application Architecture  (Martin Fowler)
  • Design patterns : elements of reusable object-oriented software (Erich Gamma)
  • Refactoring: Improving the Design of Existing Code (Martin Fowler)
  • Refactoring to Patterns 
  • Agile Software Development, Principles, Patterns, and Practices
  • Code Complete by Steve McConnel
  • Pragmatic Programmer