BASICS OF JSP

LIFE CYCLE OF JSP

A JSP page is converted into Servlet in order to service requests. The translation of a JSP page to a Servlet is called Lifecycle of JSP. JSP Lifecycle consists of following steps.

1. Translation of JSP to Servlet code.
2. Compilation of Servlet to bytecode.
3. Loading Servlet class.
4. Creating servlet instance.
5. Initialization by calling jspInit() method
6. Request Processing by calling _jspService() method
7. Destroying by calling jspDestroy() method

Web Container translates JSP code into a servlet class source(.java) file, then compiles that into a java servlet class. In the third step, the servlet class bytecode is loaded using classloader. The Container then creates an instance of that servlet class.The initialized servlet can now service request. For each request the Web Container call the _jspService()method. When the Container removes the servlet instance from service, it calls the jspDestroy() method to perform any required clean up.