Core J2EE™ Patterns: Best Practices and Design Strategies, Second Edition

Chapter 8. Integration Tier Patterns

Topics in This Chapter

• Data Access Object

• Service Activator

• Domain Store

• Web Service Broker

Data Access Object

Problem

You want to encapsulate data access and manipulation in a separate layer.

Many real-world J2EE applications implement persistent objects as Business Object (374), which use POJOs or entity beans. An application with simpler requirements might forego using business objects and instead use Session Façades (341), Application Services (357), or other helper objects that directly access and manipulate data in the persistent storage. Such business objects and application components require access to business data in a persistent store.

Most enterprise applications typically use relational database management ...