JEE Core Concepts

Internal

• JEE

Changing Application Behavior without Changing Code

The possibility to change an application's behavior without changing code is a core concern in JEE. The entire Chapter 5 in the JEE specifications is dedicated to it. The essential mechanism than makes this possible is the application component environment, also known as enterprise naming context (ENC), and the fact that the application code uses named entries in ENC to refer to configuration values and external resources. The names of those elements do not change in the code, but during the deployment, those configuration values and external resource references are mapped to deployment environment specific actual values and actual resources.

The key element here is the use of deployment descriptors, that provide this mapping.