The Java EE 5 platform introduces a simplified programming model. With Java EE 5 technology, XML deployment descriptors are now optional. Instead, a developer can simply enter the information as an annotation directly into a Java source file, and the Java EE server will configure the component at deployment and runtime. These annotations are generally used to embed in a program data that would otherwise be furnished in a deployment descriptor. With annotations, the specification information is put directly in your code next to the program element that it affects.
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