The Java EE 5 Tutorial

Java EE Components

Java EE applications are made up of components. A Java EE component is a self-contained functional software unit that is assembled into a Java EE application with its related classes and files and that communicates with other components.

The Java EE specification defines the following Java EE components:

Java EE components are written in the Java programming language and are compiled in the same way as any program in the language. The difference between Java EE components and “standard” Java classes is that Java EE components are assembled into a Java EE application, are verified to be well formed and in compliance with the Java EE specification, and are deployed to production, where they are run and managed by the Java EE server.