Evolution of Web Application
 
Role of JAVA for Server Applications
 
The J2EE specification provides a platform for enterprise applications, with complete API support for enterprise code and guarantees of portability between server implementations. Also it brings a clear division between code which deals with presentation, business logic and data
 
The J2EE specification meets the requirements of web applications because it provides:
. Affluent via servlets and built-in support for and EJBs. interaction with a sessions available in both servlets web server
. The use of EJBs to mirror the user interaction with data by providing automatic session and transaction support to EJBs operating in the EJB server.
. Entity EJBs to represent data as an object and seamless integration with the Java data access APIs
. Flexible template-based output using JSP and XML
 
APIs mean that the final web page can be generated from a user input request, which was processed by a servlet or JSP and a session EJB, which represents the user's session with the server, using data extracted from a database and put into an entity EJB.
 
Thus, the Java revolution of portable code and open APIs is conjugal with an evolution in existing products such as database, application, mail and web servers. The wide availability of products to run Java applications on the server has made this a fast-moving and very competitive market, but the essential compatibility through specifications, standard APIs and class libraries has held. It makes server-side Java a very exciting area.