JSP Life-cycle 

The Web Container also manages the life cycle of a JSP. It consists of the following phases:

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       1.      The JSP file is translated into a servlet-like implementation class – this phase is performed either when the Web application is started, or when the first request to a JSP arrives. This behavior depends on how you have configured the CompileOnStartUp property of the Web Container Service. For more information, see Specifying Compilation Time of JSP Files in the Administration Manual.

       2.      Creating an instance of the JSP.

       3.      Servicing client requests.

       4.      Destroying the JSP instance.