ajax聊天室(JSP版)4

Servlet類真的沒什麼好說的。

先寫個BaseServlet基類，以後的幾個Servlet類就直接繼承它，而不是HttpServlet。

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package org.jvk.chatroom.servlet;

 

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import org.apache.commons.logging.Log;

import org.apache.commons.logging.LogFactory;

 

public abstract class BaseServlet extends HttpServlet {

 

    public final static String USER = "user";

 

    private static final longserialVersionUID = 520131401655L;

 

    protected Log log = LogFactory.getLog(this.getClass());

 

    @Override

    public void doGet(HttpServletRequest request, HttpServletResponse response)

           throws ServletException, IOException {

       execute(request, response);

    }

 

    @Override

    public void doPost(HttpServletRequest request, HttpServletResponse response)

           throws ServletException, IOException {

       execute(request, response);

    }

 

    /**

     *由子類實現,處理GET和POST請求

     *

     *@paramrequest

     *@paramresponse

     *@throwsServletException

     *@throwsIOException

     */

    publicab stract void execute(HttpServletRequest request,

           HttpServletResponse response) throws ServletException, IOException;

 

    protected final String getValue(HttpServletRequest request, String param) {

       String str = request.getParameter(param);

       if (str == null)

           return"";

       return str;

    }

 

    private static byte[] lock = new byte[0];

 

    protected final void setNoCache(HttpServletRequest request,

           HttpServletResponse response) {

       synchronized (lock) {

           if (request.getProtocol().compareTo("HTTP/1.0") == 0)

              response.setHeader("Prama", "no-cache");

           else if (request.getProtocol().compareTo("HTTP/1.1") == 0)

              response.setHeader("Cache-Control", "no-cache");

           response.setDateHeader("Expires", 0);

       }

    }

}

---

 

package org.jvk.chatroom.servlet;

 

import java.io.IOException;

import java.util.Collection;

 

import javax.servlet.ServletException;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import javax.servlet.http.HttpSession;

 

import org.jvk.chatroom.bean.Room;

import org.jvk.chatroom.bean.User;

import org.jvk.chatroom.service.ChatroomManager;

 

public class Login extends BaseServlet {

 

    private static final longserialVersionUID = 5201314016000L;

 

    // 設置session生命週期爲1分鐘

    private static intsessionTimeOut = 60 * 1;

 

    private static final String ROOM_PAGE = "pages/chatroom.jsp";

 

    private static final String LOGIN_PAGE = "pages/login.jsp";

 

    private staticf inal String this_PAGE = "login";

 

    private static final String ERROR_PAGE = "pages/error.jsp";

 

    public void execute(HttpServletRequest request, HttpServletResponse response)

           throws ServletException, IOException {

       String userName = getValue(request, "userName");

       String roomName = getValue(request, "roomName");

       if (userName.length() < 1 || roomName.length() < 1) {

           Collection<Room> rooms = ChatroomManager.newInstance().getRooms()

                  .values();

           request.setAttribute("rooms", rooms);

           request.getRequestDispatcher(LOGIN_PAGE).forward(request, response);

       } else if (ChatroomManager.newInstance().exists(roomName, userName)) {

           log.info("該用戶已存在,請使用其他字符");

           request.setAttribute("returnURL", this_PAGE);

           request.setAttribute("errorMessage", "該用戶已存在,請使用其他字符");

           request.getRequestDispatcher(ERROR_PAGE).forward(request, response);

       } else {

           HttpSession session = request.getSession(true);

           User user = new User(userName, ChatroomManager.newInstance()

                  .getRoom(roomName));

           session.setMaxInactiveInterval(sessionTimeOut);

           user.setLastGetMessage(510);

           user.setLastGetUserList(520);

           session.setAttribute(USER, user);

           session.setAttribute("room", ChatroomManager.newInstance().getRoom(

                  roomName));

           response.sendRedirect(ROOM_PAGE);

       }

    }

 

}

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package org.jvk.chatroom.servlet;

 

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import javax.servlet.http.HttpSession;

 

import org.jvk.chatroom.bean.Message;

import org.jvk.chatroom.bean.User;

import org.jvk.chatroom.service.ChatroomManager;

 

 

public class SendMessage extends BaseServlet {

    private static final longserialVersionUID = 520131401655L;

    @Override

    public void execute(HttpServletRequest request, HttpServletResponse response) throws ServletException,

           IOException {

       HttpSession session = request.getSession(false);

       if (session == null){

           response.getWriter().write("");

           return;

       }

       synchronized (session) {

           User user = (User) session.getAttribute(USER);

           Message message = new Message();

           String to = request.getParameter("to");

           if ("all".equals(to))

              to = null;

           String content = request.getParameter("content");

           message.setContent(content);

           message.setFrom(user.getName());

           message.setTo(to);

           message.setDate(System.currentTimeMillis());

           ChatroomManager.newInstance().addMessageToRoom(message, user.getRoom());

           //假裝響應下

           response.getWriter().write("");

       }

    }

}

 

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package org.jvk.chatroom.servlet;

 

import java.io.IOException;

import java.io.PrintWriter;

import java.text.SimpleDateFormat;

import java.util.Date;

import java.util.List;

 

import javax.servlet.ServletException;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import javax.servlet.http.HttpSession;

 

import org.jvk.chatroom.bean.Message;

import org.jvk.chatroom.bean.User;

import org.jvk.chatroom.service.ChatroomManager;

 

public class GetMessage extends BaseServlet {

 

    @Override

    public void execute(HttpServletRequest request, HttpServletResponse response) throws ServletException,

           IOException {

       HttpSession session = request.getSession(false);

       if (session == null)

           return;

       synchronized (session) {

           User user = (User) session.getAttribute(USER);

           List<Message> messages = ChatroomManager.newInstance().getMessagesFromRoom(user);

           StringBuffer xml = new StringBuffer(4096);

           xml.append("<messages>");

           for (Message message : messages) {

              xml.append("<message>");

              xml.append("<from>" + message.getFrom() + "</from>");

              xml.append("<date>" + new SimpleDateFormat().format(new Date(message.getDate())) + "</date>");

              xml.append("<content>" + message.getContent() + "</content>");

              xml.append("</message>");

           }

           xml.append("</messages>");

           System.out.println("xml="+xml);

           setNoCache(request, response);

           response.setContentType("text/xml; charset=UTF-8");

           PrintWriter out = response.getWriter();

           out.print(xml);

           out.flush();

       }

 

    }

 

}

 

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package org.jvk.chatroom.servlet;

 

import java.io.IOException;

import java.io.PrintWriter;

import java.util.List;

 

import javax.servlet.ServletException;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import javax.servlet.http.HttpSession;

 

import org.jvk.chatroom.bean.User;

import org.jvk.chatroom.service.ChatroomManager;

 

public class GetUserList extends BaseServlet {

 

    @Override

    public void execute(HttpServletRequest request, HttpServletResponse response)

           throws ServletException, IOException {

       HttpSession session = request.getSession(false);

       if (session == null)

           return;

       synchronized (session) {

           User user = (User) session.getAttribute(USER);

           ChatroomManager dao = ChatroomManager.newInstance();

           List<User> list = dao.getUsersFromRoom(user);

          

           StringBuffer buffer = new StringBuffer(1024);

           buffer.append("<users>");

           for (User tempUser : list) {

              buffer.append("<user name=/"" + tempUser.getName() + "/"/>");

           }

           buffer.append("</users>");

           log.info("users=/n" + buffer);

           setNoCache(request,response);

           response.setContentType("text/xml; charset=UTF-8");

           PrintWriter out = response.getWriter();

           out.print(buffer);

           out.flush();

       }

 

    }

}

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沒有了，就這幾個類。