doGet and doPost
§ The handler methods each take two
parameters:
§ HTTPServletRequest:  encapsulates all
information regarding the browser request.
§ Form data, client host name, HTTP request headers.
§ HTTPServletResponse:  encapsulate all
information regarding the servlet response.
§ HTTP Return status, outgoing cookies, HTML response.
§ If you want the same servlet to handle both GET and
POST, you can have doGet call doPost or vice versa.
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