J2EE is Java 2 Platform Enterprise Edition. J2EE is a platform-independent, Java-centric environment from Sun for developing, building and deploying Web-based enterprise applications online.

  J2EE consists of a set of services, APIs and protocols that provide the functionality for developing multitiered, Web-based applications

Some of the key features and services of J2EE:

• At the client tier, J2EE supports pure HTML, as well as Java applets or applications.
• The Java servlet API enhances consistency for developers without requiring a graphical user interface.

  Low level services are already implemented . J2EE is well documented and understood . J2EE is a standardized and reliable software architecture . J2EE gives you a lot of flexibility . APIs used in J2EE are well documented.