The J2EE platform provides choices for graphical user interfaces across a company's intranet or on the World Wide Web. Clients can run on desktops, laptops, PDAs, cell phones, and other devices. Pure client-side user interfaces can use standard HTML and Java applets. The J2SE (Java Standard Edition) falls under Core Java. The J2EE (Java Enterprise Edition) falls under Advanced Java. You cannot create or develop an advanced java app without using Core Java. It is a prerequisite for developing all the advanced Java applications.
J2EE stands for Java 2 Platform, Enterprise Edition. J2EE is the standard platform for developing applications in the enterprise and is designed for enterprise applications that run on servers. J2EE provides APIs that let developers create workflows and make use of resources such as databases or web services. J2EE consists of a set of APIs. Developers can use these APIs to build applications for business computing.
- Portability: If you build a J2EE application on a specific platform, it runs the same way on any other J2EE-compliant platform.
- Reusability: The components in J2EE are reused, so the average size of an application is much smaller than it would be if you had to write equivalent functionality
- Security: Java technology lets programmers handle sensitive data far more securely than they can in C/C++ programs.
- Scalability: J2EE lets developers build applications that run well on both small, single-processor computers and large, multi-processor systems.
- Reliability: Many of the services (such as transaction management and monitoring) that applications need to be reliable are built into J2EE.