This is an exact quote from SUN's java technical articles @ http://java.sun.com/developer/technicalArticles/J2EE/intro_ee5/
With version 5 of the Java Platform, Enterprise Edition (Java EE, formerly referred to as J2EE), development of Java enterprise applications has never been easier or faster. J2EE 1.4, the predecessor to the Java EE 5 platform, has many powerful features. The aim of the Java EE 5 platform design has been to streamline these features and add convenience, improve performance, reduce development time, and help developers get products to market that much sooner. Here are a few of the significant changes:
- Most boilerplate requirements have been eliminated, and XML descriptors are now optional. For example, the
ejb-jar.xmldescriptor is no longer necessary in most cases.
- More defaults are available, with a special emphasis on making them meaningful. Developers now have fewer details to remember.
- Web service support is simpler, and the number of supported standards has increased.
- The EJB software programming model is significantly simpler.
- The new Java Persistence API is available to all Java platform applications, including those based on EJB technology.
- JavaServer Faces technology has been added to make web application design more convenient.