whiteboardservlet.java

J2ME MIDP_Example_Applications

// Copyright 2003 Nokia Corporation.
//
// THIS SOURCE CODE IS PROVIDED 'AS IS', WITH NO WARRANTIES WHATSOEVER,
// EXPRESS OR IMPLIED, INCLUDING ANY WARRANTY OF MERCHANTABILITY, FITNESS
// FOR ANY PARTICULAR PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE
// OR TRADE PRACTICE, RELATING TO THE SOURCE CODE OR ANY WARRANTY OTHERWISE
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// OBLIGATION OF NOKIA TO PROVIDE THE LICENSEE WITH ANY MAINTENANCE OR
// SUPPORT. FURTHERMORE, NOKIA MAKES NO WARRANTY THAT EXERCISE OF THE
// RIGHTS GRANTED HEREUNDER DOES NOT INFRINGE OR MAY NOT CAUSE INFRINGEMENT
// OF ANY PATENT OR OTHER INTELLECTUAL PROPERTY RIGHTS OWNED OR CONTROLLED
// BY THIRD PARTIES
//
// Furthermore, information provided in this source code is preliminary,
// and may be changed substantially prior to final release. Nokia Corporation
// retains the right to make changes to this source code at
// any time, without notice. This source code is provided for informational
// purposes only.
//
// Nokia and Nokia Connecting People are registered trademarks of Nokia
// Corporation.
// Java and all Java-based marks are trademarks or registered trademarks of
// Sun Microsystems, Inc.
// Other product and company names mentioned herein may be trademarks or
// trade names of their respective owners.
//
// A non-exclusive, non-transferable, worldwide, limited license is hereby
// granted to the Licensee to download, print, reproduce and modify the
// source code. The licensee has the right to market, sell, distribute and
// make available the source code in original or modified form only when
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package whiteboard;

import java.io.*;
import java.text.*;
import java.util.*;
import javax.servlet.*;
import javax.servlet.http.*;

// Simple servlet serving GET and POST requests
// Version 1.1: Security Declared in web.xml
// Uses Basic authentication
public class WhiteboardServlet
     extends HttpServlet
{

    private Whiteboard whiteboard;
    private ServletConfig config;
    private DateFormat format = null;


    public void init()
    {
        config = getServletConfig();
        String dateformat = config.getInitParameter("dateformat");
        if (dateformat != null)
        {
            try
            {
                format = new SimpleDateFormat(dateformat);
            }
            catch (Exception e)
            {
                e.printStackTrace();
                // ignore, we'll check it later
            }
        }
        if (format == null)
        {
            format = DateFormat.getTimeInstance(DateFormat.SHORT);
        }

        // init the whiteboard data structure
        whiteboard = Whiteboard.getInstance();
    }


    protected void doGet(HttpServletRequest req, HttpServletResponse resp)
        throws ServletException, java.io.IOException
    {
        // Notice that we check that the user is logged
        if (req.getRemoteUser() != null)
        {

            // Get the messages. Max 10
            Collection messages = whiteboard.getMessages();

            // Set the MIME content type to text/plain
            resp.setContentType("text/plain");

            // Collect the messages
            ValueGenerator generator = new ValueGenerator();
            generator.addValue("" + messages.size());
            Iterator i = messages.iterator();
            while (i.hasNext())
            {
                Message msg = (Message) i.next();
                generator.addValue(msg.getUser());
                generator.addValue(format.format(msg.getTimestamp()));
                generator.addValue(msg.getContent());
            }

            // print the text
            ServletOutputStream out = resp.getOutputStream();
            out.println(generator.getString());
        }
        else
        {
            resp.sendError(HttpServletResponse.SC_UNAUTHORIZED);
        }
    }


    protected void doPost(HttpServletRequest req, HttpServletResponse resp)
        throws ServletException, java.io.IOException
    {
        // Notice that we check that the user is logged
        if (req.getRemoteUser() != null)
        {
            String user = req.getRemoteUser();
            String msg = req.getParameter("msg");

            if (msg != null)
            {
                // add a new message
                whiteboard.addMessage(new Message(user, new Date(), msg));
                // delegate to doGet to create the response
                doGet(req, resp);
            }
            else
            {
                // msg parameter is required
                resp.sendError(HttpServletResponse.SC_BAD_REQUEST, "Missing msg parameter");
            }
        }
        else
        {
            resp.sendError(HttpServletResponse.SC_UNAUTHORIZED);
        }
    }
}