The Enterprise JavaBeans Specification v. 3.0 introduces a simplified, annotation based API for EJB injection and lookup. EJB 3.0 are now POJOs and can be injected in other components (such as EJBs and Servlets) using simple annotations. EJB 3.0 is one of many other POJO-based specifications that made it to Java EE 6, such as JSR-229 "Contexts and Dependency Injection for the Java EE Platform" (formerly known as "Web Beans"). Java EE has never been so easy!

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Java Code Geeks: An Introduction to EJB 3.0 Injection and Lookup