// // This program is distributed in the hope that it will be useful, // but WITHOUT ANY WARRANTY; without even the implied warranty of // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the // GNU General Public License for more details.
// // To obtain a copy of the GNU General Public License write to the Free // Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
import java.io.IOException ;
import java.io.PrintWriter ;
import javax.servlet.ServletException ;
import javax.servlet.http.* ;
/**
* HelloWorldServlet simply displays "Hello World".
*
* @author Robert Judd
*/
public class HelloWorldServlet extends HttpServlet {
/**
* In order to write a useful servlet you must implement at least one of
* the methods doGet or doPost. If you don't care
* about the difference between GET and POST requests, then
* you can just implement one, say doGet and then set the other to call it
* (see doPost below).
*
* @param req a HttpServletRequest value
* @param res a HttpServletResponse value
* @exception ServletException if an error occurs
* @exception IOException if an error occurs
*/
public void doGet(HttpServletRequest req, HttpServletResponse res)
throws ServletException, IOException {
// You should set the content type of the response - the following lets
// the browser know to expect an html page. Any valid content type may
// be returned, for example you can set it to "application/pdf" and write
// a PDF file in response to the request. If your browser knows about
// PDF files, then it will run acroread or some other viewer to display
// the file
res.setContentType("text/html") ;
// Next you must get the PrintWriter in order to output data
PrintWriter out = res.getWriter() ;
// Finally you can write any text to the stream
out.println("
doGet as
* shown below (commented out). If you try to call this servlet with a POST
* request, then you will get a "Bad Request" error from the server.
*
* I only usually bother implementing doPost if the data sent with the
* request is more than just "name=value" pairs from a form - for example
* a file, or a Java Object sent from an applet.
*
* @param req a HttpServletRequest value
* @param res a HttpServletResponse value
* @exception ServletException if an error occurs
* @exception IOException if an error occurs
*/
// public void doPost(HttpServletRequest req, HttpServletResponse res)
// throws ServletException, IOException {
// doGet(req, res) ;
// }
}// HelloWorldServlet