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The easiest way to
define a servlet is to
extend the HttpServlet class, shadowing the doGet method.
That method has two parameters: the
request parameter's value is a
class instance that contains information about the request (ignored in the
following example); the
response parameter's value is a class
instance that your program uses to convey information back to the browser
from which the request originated.
The setContentType method prepares the response instance to receive
the text of an HTML page. The getWriter method obtains an output stream
on which to write text, which happens to be an instance of the
PrintWriter class.
Once doGet completes, the servlet server returns the information contained
within the response instance to the client, to be displayed by the browser
as a new HTML page. Evidently, doGet is so named because it
gets a new HTML page.
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
public class GetCriticFormServlet extends HttpServlet {
public void doGet (HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
response.setContentType("text/html");
PrintWriter output = response.getWriter();
output.println("<HTML><HEAD><TITLE>");
output.println("You be the critic!");
output.println("</TITLE></HEAD><BODY>");
// HTML content, such as the form shown in Segment 1043,
// printed to output stream here using println
output.println("</BODY></HTML>");
output.flush();
}
}