Completely updated and revised, this is the second edition of the best-seller Core J2EE Patterns. J2EE has become the platform of choice for Web-centric distributed enterprise application development. Expert consultants from the Sun Java Center have identified powerful J2EE design patterns that lead to applications with superior performance, scalability, and robustness. This book brings those design patterns together, sharing Sun's best practices for development with Java Server Pages (JSP), Servlets, EJB, and other J2EE technologies. It presents a complete catalog of J2EE patterns encapsulating proven and recommended designs for common J2EE-related problems, organized into presentation tier, business tier and integration tier solutions. This second edition introduces new patterns, new refactorings, new patterns for using XML as well as new patterns for J2EE Web services. The authors also identify bad practices to be avoided. Finally, it presents an end-to-end multi-tier case study covering every stage of enterprise development.