Web programming

Units WEB1P and WEB2P

Enterprise Java Beans (EJB)

Background

Enterprise Java Beans (EJB) have been part of Java EE since 1999, but it wasn't until the release of EJB version 3.0 (part of Java EE 5) in 2006 that they really became easy to use. The older versions had used a complicated set of local and remote interfaces to manage access to EJBs. Version 3 made EJBs out of POJOs (Plain Old Java Objects), considerably simplifying things.

EJBs are server-side components and require an EJB container in which to operate. The container provides the management structure for creating, naming, sharing and shutting down EJBs. Without a container, the programmer would have to write a lot of code to do this (and other things) themselves. The container automates this (easing development by performing default - common case - configuration automatically). GlassFish is the reference implementation for the EJB specification.

EJBs are closely tied with the Java Persistence API (JPA) and provide many of the facilities that a JPA application needs to run.

The EJB container is a runtime environment that provides a number of core features that are common to many applications (see container functionality below)

What do I need to know about EJBs?

EJB basics

EJB details

Container functionality

Reading

 

Last updated by Prof Jim Briggs of the School of Computing at the University of Portsmouth

 
The web programming units include some material that was formerly part of the WPRMP, WECPP, WPSSM and WEMAM units.