Overriding JSP Server Generated Servlet Subclass

Q

How do I have the JSP-generated servlet subclass be my own custom servlet class, instead of the default?

✍: FYICENTER.com

A

One should be very careful when having JSP pages extend custom servlet classes as opposed to the default one generated by the JSP engine. In doing so, you may lose out on any advanced optimization that may be provided by the JSPengine.

In any case, your new superclass has to fulfill the contract with the JSP engine by: Implementing the HttpJspPage interface, if the protocol used is HTTP, or implementing JspPage otherwise Ensuring that all the methods in the Servlet interface are declared final.

Additionally, your servlet superclass also needs to do the following:

The service() method has to invoke the _jspService() method
The init() method has to invoke the jspInit() method
The destroy() method has to invoke jspDestroy()

If any of the above conditions are not satisfied, the JSP engine may throw a translation error.

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