javaweb写的在线聊天应用

　　写这个玩意儿就是想练练手， 用户需要登陆才能在线聊天，不要依赖数据库， 不需要数据库的操作， 所有的数据都是保存在内存中， 如果服务器一旦重启，数据就没有了；

　　登录界面：

　　

　　聊天界面：

　　

　　左侧是在线的用户列表， 右侧是聊天的内容， 内容的格式为 “作者 ： 内容”；

　　点击button可以发布聊天信息；

　　

　　使用的是spring搭建的框架，基于tomcat的服务器；

　　web.xml的配置如下：

<?xml version="1.0" encoding="UTF-8"?>
<web-app version="3.0" 
    xmlns="http://java.sun.com/xml/ns/javaee" 
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
    xsi:schemaLocation="http://java.sun.com/xml/ns/javaee 
    http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd">
  <display-name></display-name>    
  <welcome-file-list>
    <welcome-file>index.htm</welcome-file>
  </welcome-file-list>
  
  <servlet>
    <servlet-name>test</servlet-name>
    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
    <load-on-startup>1</load-on-startup>
    </servlet>

    <servlet-mapping>
    <servlet-name>test</servlet-name>
    <url-pattern>*.htm</url-pattern>
    </servlet-mapping>

    <listener>
        <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
    </listener>
    
    <filter>
        <filter-name>CharacterEncodingFilter</filter-name>
        <filter-class>com.nono.Filter.CharacterEncodingFilter</filter-class>
        <init-param>
            <param-name>encoding</param-name>
            <param-value>UTF-8</param-value>
        </init-param>
    </filter>
    
    <filter>  
        <filter-name>SecurityServlet</filter-name>  
        <filter-class>com.nono.SecurityServlet</filter-class>  
    </filter>  
    <filter-mapping>  
        <filter-name>SecurityServlet</filter-name>  
        <url-pattern>*.htm</url-pattern>  
    </filter-mapping>
    

    <!-- 
        使用Spring中的过滤器解决在请求和应答中的中文乱码问题 
    <filter>
        <filter-name>characterEncodingFilter</filter-name>
        <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
        <init-param>
            <param-name>encoding</param-name>
            <param-value>utf-8</param-value>
        </init-param>
        <init-param>
                强制转换编码(request和response均适用) 
            <param-name>ForceEncoding</param-name>
            <param-value>true</param-value>
        </init-param>
    </filter>
    -->
   
    <context-param>
        <param-name>
        contextConfigLocation
        </param-name>
        <param-value>
        /WEB-INF/test-servlet.xml
        </param-value>
    </context-param>
</web-app>

　　conteConfigLocation的配置为：

<?xml version="1.0" encoding="UTF-8" ?>
<beans xmlns="http://www.springframework.org/schema/beans"
 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:p="http://www.springframework.org/schema/p"
 xmlns:context="http://www.springframework.org/schema/context"
 xmlns:aop="http://www.springframework.org/schema/aop"
 xmlns:tx="http://www.springframework.org/schema/tx"
 xmlns:mvc="http://www.springframework.org/schema/mvc"
 xmlns:task="http://www.springframework.org/schema/task"
 xsi:schemaLocation="http://www.springframework.org/schema/beans
      http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
      http://www.springframework.org/schema/context
      http://www.springframework.org/schema/context/spring-context-3.0.xsd
      http://www.springframework.org/schema/tx
      http://www.springframework.org/schema/tx/spring-tx-3.0.xsd
      http://www.springframework.org/schema/aop
      http://www.springframework.org/schema/aop/spring-aop-3.0.xsd
      http://www.springframework.org/schema/mvc
      http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd
      http://www.springframework.org/schema/task
      http://www.springframework.org/schema/task/spring-task-3.0.xsd">
    

    <context:annotation-config> </context:annotation-config>
    <context:component-scan base-package="com.nono" > </context:component-scan>
    
    <bean id="viewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <property name="suffix">
            <value>.jsp</value>
        </property>
    </bean>
</beans>

　　

　　整个项目的结构为一个主路由， 四个po层,  两个过滤器：

　　

　　界面的用户列表和用户内容列表用了ajax刷新， 感觉不错的说：

<!--
    修改pageEncoding为 utf-8
 -->
<%@ page language="java" import="java.util.*"  pageEncoding="utf-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
  <head>
    <base href="<%=basePath%>">
    
    <title>login</title>
    <meta charset="utf-8">
    <link href="http://cdn.bootcss.com/bootstrap/3.3.5/css/bootstrap.min.css" rel="stylesheet">
    <script src="http://cdn.bootcss.com/jquery/1.9.0/jquery.js"></script>
  </head>
  <style>
      html,body,.bg{
          height:100%;
      }
      .bg{
          background:url(imgs/bg.jpeg);
      }
  </style>
  <body>
        <div class="container-fuild bg">
            <div class="row">
                <div class="col-sm-4">
                    <div class="page-header">
                        <h2>
                            list
                        </h2>
                        <ol id="list">
                            <li>name—</li>
                            <li>name—</li>
                            <li>name—</li>
                            <li>name—</li>
                        </ol>
                    </div>
                </div>
                <div class="col-sm-8">
                        <h2>
                            content
                        </h2>
                    <div id="con" class="page-header">
                      <p>
                          <b>haha:</b>
                          <big>
                              say someting
                          </big>
                      </p>
                      <p>
                          <b>haha:</b>
                          <big>
                              say someting
                          </big>
                      </p>
                    </div>
                    <form>
                      <div class="form-group">
                        <label for="text">enter text</label>
                        <input type="text" id="answer" class="form-control" id="text" placeholder="text">
                      </div>
                      <button type="button" id="sb" class="btn btn-default">Submit</button>
                    </form>
                </div>
            </div>
        </div>
        <script>
            $("#sb").click(function() {
                $.post("chat.htm", "content="+ $("#answer").val(), function(data) {
                    console.log(data);
                });
            });
            
            function Get(url , el, fn) {
                this.post = function() {
                    $.post(url, function(data) {
                        data = JSON.parse(data);
                        var html = "";
                        $.each(data,function(i, e) {
                            html += fn(i,e);
                        });
                        $(el).html( html );
                    });
                };
            };
            
            (function() {
            
                var list = new Get("getList.htm", "#list", function(i, e) {
                    return  "<li>" + e.name + "</li>";
                });
                
                var content =  new Get("getContent.htm", "#con", function(i, e) {
                    return "<p><b>"+ e.name +" : </b><big>"+ e.content +"</big></p>";
                });
                
                setInterval(function() {
                    list.post();
                    content.post();
                },1000);
                
            })();
        </script>
  </body>
</html>

　　权限控制的话我们可以用到fileter：

package com.nono;

import java.io.IOException;
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

import com.nono.po.User;

public class SecurityServlet extends HttpServlet implements Filter {
    private static final long serialVersionUID = 1L;

    public void doFilter(ServletRequest arg0, ServletResponse arg1, FilterChain arg2) throws IOException, ServletException {
           HttpServletRequest request=(HttpServletRequest)arg0;   
           HttpServletResponse response  =(HttpServletResponse) arg1;    
           HttpSession session = request.getSession();
           User user = (User) session.getAttribute("user");
           String url=request.getRequestURI();   
           //如果用户信息不是空的， 或者要访问的是登陆的界面(get,post的方式包含了login字符串);
           if( user!=null  || url.indexOf("login")>-1 ) {
               arg2.doFilter(arg0, arg1);   
               return;
           }else{
               //余下的全跳到登陆界面
               response.sendRedirect(request.getContextPath() + "/login.htm");
               return;
           }
    }
    public void init(FilterConfig arg0) throws ServletException {
    }

}

　　路由控制和服务放到了一起， 因为权限控制使用过滤器处理， 所以在路由里面我们就不用关心用户的消息， 只要处理业务逻辑就好了：

package com.nono.Controller;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.Vector;

import javax.jms.Session;
import javax.print.DocFlavor.STRING;
import javax.print.attribute.HashAttributeSet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

import net.sf.json.JSONArray;

import org.omg.CORBA.PUBLIC_MEMBER;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.ResponseBody;

import com.nono.po.Content;
import com.nono.po.Contents;
import com.nono.po.User;
import com.nono.po.Users;

@Controller
public class MainController {
    //用户和用户组;
    @Autowired
    Users users;
    
    @Autowired
    Contents contents;
    
    @RequestMapping(value="login", method=RequestMethod.GET)
    public String login (HttpServletRequest request) {
        return "login";
    }

    
    @RequestMapping(value="login", method=RequestMethod.POST)
    public String loginPOST ( HttpServletRequest request, HttpServletResponse response ) {
        
        String string = "login";
        String name = (String) request.getParameter("name");
        Boolean flag = true;
        //如果名字不是空的话;
        if( !name.equals("") ) {
            Vector vector = users.getList();
            for(int i=0; i< vector.size(); i++) {
                User user = (User) vector.elementAt(i);
                if( user.getName().equals( name ) ) {
                    flag = false;
                };
            };
        };
        
        //用户名不存在
        if( flag ) {
            User user = new User();
            user.setName( name );
            HttpSession session = request.getSession(true);
            //设置Session的过期时间为10分钟
            session.setMaxInactiveInterval(600);
            //设置seesion中的用户信息;
            session.setAttribute("user", user);
            //添加用户;
            users.addUser( user );
            
            //加入的提示;
            Content content = new Content();
            content.setName( name );
            content.setContent( "enter the chat room!" );
            contents.addContent( content  );
            
            string = "chat";
            return string;
        }else{
            //用户名已经存在
            request.setAttribute("info", "用户名已经存在1");
            string = "login";
            return string;
        }
    }
    
    @RequestMapping(value="chat", method=RequestMethod.GET)
    public String main (HttpServletRequest request) {
        String string = "chat";
        return string;
    }
    
    @RequestMapping(value="chat", method=RequestMethod.POST)
    @ResponseBody
    public String chat(HttpServletRequest request) {
        String string = (String) request.getParameter("content");
        HttpSession session = request.getSession();
        //设置seesion中的用户信息;
        User user = (User) session.getAttribute("user");
        String name = user.getName();
        Content content = new Content();
        content.setName( name );
        content.setContent( string );
        contents.addContent( content  );
        return "true";
    }
    
    @RequestMapping(value="getList", method=RequestMethod.POST, produces = "text/html;charset=UTF-8")
    @ResponseBody
    public String getList( HttpServletRequest request) {
        return JSONArray.fromObject( users.getList() ).toString();
    }
    
    @RequestMapping(value="getContent", method=RequestMethod.POST, produces = "text/html;charset=UTF-8")
    @ResponseBody
    public String getArrayList() {
        ArrayList list = (ArrayList) contents.getContents();
        ArrayList result = new ArrayList();
        for( int i= 0; i< list.size(); i++ ) {
            HashMap<String,String> hashMap = new HashMap();
            hashMap.put("name", ((Content)list.get(i)).getName());
            hashMap.put("content", ((Content)list.get(i)).getContent());
            result.add( hashMap );
        };
        return JSONArray.fromObject( result ).toString();
    }
    
}

　　有哪位大神告诉我为什么中文各种乱码， 在界面中的utf-8也设置， @ResponseBody的也设置了， 还是乱码， encodeURIComponent过的也是乱码， 坑爹啊；

　　

作者： NONO
出处：http://www.cnblogs.com/diligenceday/
QQ：287101329