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service ( ) method overriding or overloading?

Thambi Rajah
Ranch Hand

Joined: Jul 19, 2002
Posts: 36
When there is a request from a client, the Servlet Container calls
service(ServletRequest req, ServletResponse res) method of HttpServlet class. This method in turn
will call service(HttpServletRequest req, HttpServletResponse res) method of HttpServlet class.
Suppose, we have a user-defined class TestServlet(see code below), which extends HttpServlet, has a method
service(HttpServletRequest req, HttpServletResponse res).
My question is whether service(req,res) method in TestServlet is overriding methodB in HttpServlet class or
an overloading method to the methods methodA and methodB in HttpServlet class?
Any clarification on this matter is appreciated.
Thanks in advance
Kyle Tang
Ranch Hand

Joined: Aug 22, 2002
Posts: 78
since TestServlet is extending HttpServlet, so is override. when subclass has a method which has the same method signature as in the super class, it is override's definition.
in this case, if TestServlet defines its own service(HttpServletRequest, HttpServletResponse) then you need to be careful whether you want your do***() to be called.
[ September 27, 2002: Message edited by: Kyle Tang ]

Kyle Tang<br />SCJP 91<br />SCWCD 96<br />SCBCD 95
Thambi Rajah
Ranch Hand

Joined: Jul 19, 2002
Posts: 36
Hello Kyle,
Thanks for your prompt response.
I was thinking as the same way as you explained. I got confused when I followed the discussion on the following
where it says:

Keep in mind too that the service method in the code is overloading the public method it gets from its HttpServlet. The
public method in HttpServlet takes a ServletResponse and a ServletRequest as its parameters not HttpServletResponse and
HttpServletRequest. All the public method does is dispatch the request to the protected method after converting the request
and response objects to Http objects. So, in reality, the method in the code posted will never be called, but the method it
overloads will be, along with the protected method the servlet will inherit from HttpServlet.
no more user
Ranch Hand

Joined: Aug 07, 2002
Posts: 39
hi Thambi,
you can override an overloaded method!!
the service method continue overloaded in subclass, after overriding..
hope this help..
I agree. Here's the link:
subject: service ( ) method overriding or overloading?
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