Now after we saw what components are contained in projects and modules and how to find and construct reasonably sized modules and packages, let's get more down to earth and discuss the topic of Java EE. It certainly makes sense to think about the business concerns first and follow the practices of Domain-Driven Design to identify bounded context and modules with all the contents of our domain.

Let's see how to realize the identified business modules and use cases.

This chapter will cover:

• How to implement application use case boundaries
• What the Java EE core domain components are
• Design patterns and Domain-Driven Design with Java EE
• Application communication
• How to integrate persistence
• Technical cross-cutting concerns and asynchronous behavior
• Concepts and principles of Java EE
• How to achieve maintainable code