I believe they could help you with your day-to-day GWT development so I decided to aggregate them all at this post.
So, here they are:
(NOTE: Please let us know if some of these tips are outdated so that we remove them from the list)
Java Platform, Enterprise Edition is a widely used platform for enterprise server programming in the Java programming language.
This book covers exciting recipes on securing, tuning and extending enterprise applications using a Java EE 6 implementation.The book starts with the essential changes in Java EE 6. Then they will dive into the implementation of some of the new features of the JPA 2.0 specification, and look at implementing auditing for relational data stores.They will then look into how they can enable security for their software system using Java EE built-in features as well as using the well-known Spring Security framework. They will then look at recipes on testing various Java EE technologies including JPA, EJB, JSF, and Web services.Next they will explore various ways to extend a Java EE environment with the use of additional dynamic languages as well as frameworks.At the end of the book, they will cover managing enterprise application deployment and configuration, and recipes that will help you debug problems and enhance the performance of your applications.