Enterprise JavaBeans (EJB) was introduced for building distributed components. When it arrived it came with a promise to solve all issues and complexities of CORBA. EJB being the heart of J2EE went through several major revisions and got fattened with many features. Early on, most of the developers fell in love with EJB and used EJB in their application even it did not make any sense. “Blame it on EJB” has been the attitude for many developers when their projects did not scale well and they used EJB.

Development of EJB was never easier and it became more complex with every release of EJB specification. EJB has been compared with an elephant due to its complexity and heavy weight nature. Many developers feel EJB is like an extra layer of sugar syrup on a doughnut. In an age where low carb and Atkins diet is craze, the EJB expert committee has no option but to produce a low carb incarnation of EJB thus simplifying the development of EJB. EJB 3.0 expert committee released a sample picture of the lightweight model during JavaOne 2004 when it announced release of first public draft of EJB 3.0 Specification.

Here is the link to the article Simplifying EJB Development with EJB 3.0