So, What EJB Is All About
What is EJB? Why is it important? Is it rocket science? These are the types of questions that you may ask when you start to learn about EJB. In fact, EJB specification has been gaining a great interest since its first version was announced back in 1998. By this time, as the enterprise systems were growing rapidly, the need for a standardized framework to handle the increased complexity of this type of systems was also increasing. EJB standard fits just well in this area because it addresses the common problems that face the design of backend applications. The standard describes how business logic is encapsulated and addresses transactions integrity, object relational mapping and system scalability.
Early versions of EJB implementations were adopted quickly by many companies and enterprise systems were migrated to use the new standard, however, and just like any software systems, problems started to appear and criticism of the whole framework arouse as software developers started to complain about the difficulty of using the APIs and the overall slow performance of the system.
The recent version of the EJB specification, namely EJB 3, was a complete makeover. It eliminated a lot of complexities found in its predecessors and introduced the use of new design paradigms like dependency injection (DI) to provide a more reliable and usable framework. It also offered the newly designed Java persistence API (JPA) for database integration.
Whether to use EJB or not depends solely on the nature of the application that you are implementing. EJB was designed to facilitate and speed up the process of developing large distributed enterprise applications. Such type of systems usually include large amounts of user data, a lot of system integration with external systems, numerous amounts of transactions and integration with one or more databases. So if your application is one of those, EJB will keep your life simple if you really know how to use it right. Moreover, this technology is continuously improving and is widely acceptable by major IT companies and strongly supported by a huge community, the thing that gives us confidence that it will not be discontinued anytime soon.