The javax.servlet package provides basic interfaces and classes for a Servlet program.
Life cycle
init → service → doXxxx → destroy
The service method
Any request to a Servlet goes through a service method.
The service method is defined in the javax.servlet.Servlet interface.
The doXxxx method
These methods are defined in the javax.servlet.http.HttpServlet class.
In a Servlet, these methods can be overridden.
doGet HTTP GET request
doPost HTTP POST request
doPut HTTP PUT request
doHead HTTP HEAD request
doDelete HTTP DELETE request
doOptions HTTP OPTIONS request
doTrace HTTP TRACE request
