JSP前端+Java后台ChatRoom

Model：用户信息

package com.chat.model;
import java.util.Vector;
/**
 *采用单例模式来管理用户信息
 * @author Tom
 */
public class UserInfo {
    private static UserInfo user=new UserInfo();
    private Vector vector=null;

    private UserInfo(){
        this.vector=new Vector();
    }
    public static UserInfo getInstance(){
        return user;
    }

    public boolean addUser(String user){
         if(user!=null){
             this.vector.add(user);
             return true;
         }else{
             return false;
         }
    }

    //获取用户列表

    public Vector getList(){
        return this.vector;
    }
    //移除用户

    public void removeUser(String user){
       if(user!=null){
           vector.removeElement(user);
       }
    }

}

业务处理类：

package com.chat.servlet;
import com.chat.model.UserInfo;
import javax.servlet.http.HttpSessionBindingEvent;

public class UserListener implements javax.servlet.http.HttpSessionBindingListener {

    private String user;
    private UserInfo container=UserInfo.getInstance();

    public UserListener(){
         user="";
    }
    //设置在线监听人员

    public void setUser(String user){
        this.user=user;
    }
    //获取在线监听

     public String getUser(){
         return this.user;
     }
     //当session有对象加入时执行的方法

    public void valueBound(HttpSessionBindingEvent event) {
            System.out.println("上线用户："+this.user);
    }
    //当session对象有用户移除的时候执行的方法

    public void valueUnbound(HttpSessionBindingEvent event) {
      System.out.println("下线用户："+this.user);
      if(user!=""){
          container.removeUser(user);
      }
    }

}

消息处理类：

package com.chat.servlet;
import java.util.*;
import com.chat.model.UserInfo;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.Vector;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

public class Messages extends HttpServlet {

    protected void processRequest(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        response.setContentType("text/html;charset=UTF-8");
        String action=request.getParameter("action");

        try {
            if("loginRoom".equals(action)){ //登录时，写入系统公告

                this.loginRoom(request, response);
            }else if("sendMessage".equals(action)){ //发送聊天信息

                this.sendMessages(request, response);
            }else if("getMessages".equals(action)){ //从XML文件中读取聊天信息

                 this.getMessages(request, response);
            }
        } finally {

        }
    }

    //将页面重定向到显示聊天信息的页面

    public void getMessages(HttpServletRequest request,HttpServletResponse response) {
            response.setContentType("text/html;charset=UTF-8");
            try{
                request.getRequestDispatcher("content.jsp").forward(request, response);
            }catch(Exception ex){
                 Logger.getLogger(Messages.class.getName()).log(Level.SEVERE, null, ex);
            }
    }

    // 登录时，写入系统公告

     public void loginRoom(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
         response.setContentType("text/html;charset=UTF-8");
         HttpSession session=request.getSession();
         String username=request.getParameter("username");    //获得登录用户名

     UserInfo user=UserInfo.getInstance();        //获得UserInfo类的对象

     session.setMaxInactiveInterval(600);        //设置Session的过期时间为10分钟

          Vector vector = user.getList();
         boolean flag = true; //标记是否登录的变量

         //判断用户是否登录

         System.out.println("vector的size:" + vector.size());

         if(vector!=null && vector.size()>0){
             for(int i=0;i<vector.size();i++){
                 System.out.println("vector"+i+""+vector.elementAt(i)+" user"+username);
                 if(username.equals(vector.elementAt(i))){
                     PrintWriter out;
                     try{
                         out = response.getWriter();
                         out.println("alert('该用户已经登录！');window.location.href='index.jsp';");
                     }catch(IOException e){
                         e.printStackTrace();
                     }
                     flag=false;
                     break;
                 }
             }
         }

         //保存用户信息

         if(flag){
             UserListener ul=new UserListener();    //创建UserListener的对象

             ul.setUser(username); //添加用户

             user.addUser(ul.getUser());
             session.setAttribute("user", ul); //将UserListener对象绑定到session对象中

             session.setAttribute("username",username); //保存当前登录的用户名

             session.setAttribute("loginTime",new Date().toLocaleString()); //保存登录时间


             ServletContext application =getServletContext();

             String sourceMessage="";
             if(null!=application.getAttribute("message")){
                 sourceMessage=application.getAttribute("message").toString();
             }

             sourceMessage+="系统公告:" + username + "走进聊天室!";
              application.setAttribute("message",sourceMessage);
              try{
                  request.getRequestDispatcher("login_ok.jsp").forward(request, response);
              }catch(Exception ex){
                  Logger.getLogger(Messages.class.getName()).log(Level.SEVERE, null,ex);
              }
         }
     }
     // 发送聊天信息

      public void sendMessages(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
            response.setContentType("text/html;charset=UTF-8");
            request.setCharacterEncoding("UTF-8");
            Random random=new Random();
            String from = request.getParameter("from"); //发言人

            String face =request.getParameter("face"); //表情

            String to =request.getParameter("to"); //接收者

             String color = request.getParameter("color"); //字体颜色

            String content = request.getParameter("content"); //发言内容

            String sendTime = new Date().toLocaleString(); //发言时间

            ServletContext application = getServletContext();
            String sourceMessage = application.getAttribute("message").toString();

              try {
                //发言时间

                sourceMessage += "" + from + "" + face + "对[" + to + "]说：" + "" + content + "（" + sendTime + "）";
                application.setAttribute("message", sourceMessage);
                request.getRequestDispatcher("Messages?action=getMessages&nocache=" + random.nextInt(10000)).forward(request, response);
            } catch (Exception ex) {
                Logger.getLogger(Messages.class.getName()).log(Level.SEVERE, null, ex);
            }




      }




    @Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        processRequest(request, response);
    }

    /**
     * Handles the HTTP POST method.
     * @param request servlet request
     * @param response servlet response
     * @throws ServletException if a servlet-specific error occurs
     * @throws IOException if an I/O error occurs
     */
    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        processRequest(request, response);
    }


    @Override
    public String getServletInfo() {
        return "Short description";
    }//

}

Filter：

package com.chat.filter;
import java.io.IOException;
import javax.servlet.*;
/**
 *
 * @author Tom
 */
public class CharacterEncodingFilter implements Filter{

    protected String encoding=null;
    protected FilterConfig filterConfig=null;
    public void init(FilterConfig filterConfig) throws ServletException {
        this.filterConfig=filterConfig;
        this.encoding=filterConfig.getInitParameter("encoding"); //从web.xml中获取编码格式参数

    }

    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
        if(encoding!=null){
            request.setCharacterEncoding(encoding); //设置请求编码

            response.setContentType("text/html;charset="+encoding); //设置响应编码

        }
        chain.doFilter(request, response);
    }

    public void destroy() {
        this.encoding=null;
        this.filterConfig=null;
    }
}

web.xml:

<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.5" xmlns="" xmlns:xsi="" xsi:schemaLocation=" /web-app_2_5.xsd">
    <servlet>
        <servlet-name>Messages</servlet-name>
        <servlet-class>com.chat.servlet.Messages</servlet-class>
    </servlet>
    <servlet-mapping>
        <servlet-name>Messages</servlet-name>
        <url-pattern>/Messages</url-pattern>
    </servlet-mapping>
    <session-config>
        <session-timeout>
            30
        </session-timeout>
    </session-config>
    <welcome-file-list>
        <welcome-file>index.jsp</welcome-file>
    </welcome-file-list>
    <filter>
        <filter-name>CharacterEncodingFilter</filter-name>
        <filter-class>com.chat.filter.CharacterEncodingFilter</filter-class>
        <init-param>
            <param-name>encoding</param-name>
            <param-value>UTF-8</param-value>
        </init-param>
    </filter>
    <filter-mapping>
        <filter-name>CharacterEncodingFilter</filter-name>
        <url-pattern>/*</url-pattern>
        <dispatcher>REQUEST</dispatcher>
        <dispatcher>FORWARD</dispatcher>
    </filter-mapping>

</web-app>

附件：

 chatroom.rar