java实现手机扫描二维码进行登录-程序员宅基地

技术标签: ViewUI  java  后端  javascript  

转自:http://www.daxueit.com/article/2581.html

 

项目结构:

实现流程:

pc端:

1:打开二维码登录网页index.html

2:index.html调用GetQrCodeServlet

3:GetQrCodeServlet干2件事

  a:生成随机的uuid,是一个唯一标识,该标识贯穿整个流程

  b:生成二维码图片,二维码信息:http://60.28.201.37:8380/QrCodeLoginPro/Login.html?uuid=" + uuid

4:index页面展示二维码

5:index页面调用LongConnectionCheckServlet进行长连接轮询操作,参数为uuid

6:LongConnectionCheckServlet只干1件事

  a:拿到uuid后循环检查loginUserMap中uuid是否不为null。

7:如果为null则代表没有登录,index.html将继续进行轮询

  ps: LongConnectionCheckServlet 一个长连接请求检测登录状态

    loginUserMap 是一个静态的map结构的登录池,uuid为key , 登录信息为value

手机端:

1:扫描pc端的二维码

2:打开二维码中的网页 http://60.28.201.37:8380/QrCodeLoginPro/Login.html?uuid=" + uuid

3:登录,将uname upwd uuid 传递给登录程序PhoneLoginServlet

4:PhoneLoginServlet干2件事

  a:检测登录

  b:登录成功后将登录信息插入到loginUserMap中去,uuid为key

pc端:

  1:继续轮询检测uuid中是否为null

  2:登录后的uuid中就不为null了,此时LongConnectionCheckServlet停止循环,返回登录状态。

代码:

cn.kuwo下的3个servlet

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package cn.kuwo;
 
import java.io.IOException;
import java.io.PrintWriter;
import java.util.Date;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import cn.kuwo.util.TwoDimensionCode;
 
/**
  * 生成二维码图片以及uuid
  * @author zijuntang
  *
  */
public class GetQrCodeServlet extends HttpServlet {
     private static final long serialVersionUID = 1L;
     protected void doGet(HttpServletRequest request,
             HttpServletResponse response) throws ServletException, IOException {
         doPost(request, response);
     }
     protected void doPost(HttpServletRequest request,
             HttpServletResponse response) throws ServletException, IOException {
         PrintWriter out = response.getWriter();
         
         //生成唯一ID
         int uuid = ( int ) (Math.random() * 100000 );
         //二维码内容
         String content = "http://60.28.201.37:8380/QrCodeLoginPro/Login.html?uuid=" + uuid;
         //生成二维码
         String imgName =  uuid + "_" + ( int ) ( new Date().getTime() / 1000 ) + ".png" ;
         String imgPath = "/home/web/apache/htdocs/QrCodeLogin/" + imgName;
         TwoDimensionCode handler = new TwoDimensionCode();
         handler.encoderQRCode(content, imgPath, "png" );
         
         //生成的图片访问地址
         String qrCodeImg = "http://60.28.201.37/QrCodeLogin/" + imgName;
         String jsonStr = "{\"uuid\":" + uuid + ",\"qrCodeImg\":\"" + qrCodeImg + "\"}" ;
         out.print(jsonStr);
         out.flush();
         out.close();
     }
}
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package cn.kuwo;
 
import java.io.IOException;
import java.io.PrintWriter;
import java.util.Date;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import cn.kuwo.vo.LoginUserVo;
import cn.kuwo.vo.UserVo;
 
/**
  * 用长连接,检查登录状态
  * @author zijuntang
  *
  */
public class LongConnectionCheckServlet extends HttpServlet {
     private static final long serialVersionUID = 1L;
     public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
         doPost(request, response);
     }
     public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
         String uuid = request.getParameter( "uuid" );
         String jsonStr = "" ;
         System.out.println( "in" );
         System.out.println( "uuid:" + uuid);
         long inTime = new Date().getTime();
         Boolean bool = true ;
         while (bool) {
             try {
                 Thread.sleep( 1000 );
             } catch (InterruptedException e) {
                 e.printStackTrace();
             }
             //检测登录
             UserVo userVo = LoginUserVo.getLoginUserMap().get(uuid);
             System.out.println( "userVo:" + userVo);
             if (userVo != null ){
                 bool = false ;
                 jsonStr = "{\"uname\":\"" +userVo.getUname()+ "\"}" ;
                 LoginUserVo.getLoginUserMap().remove(uuid);
             } else {
                 if ( new Date().getTime() - inTime > 5000 ){
                     bool = false ;
                 }
             }
         }
         System.out.println( "login ok : " + jsonStr);
         PrintWriter out = response.getWriter();
         out.print(jsonStr);
         out.flush();
         out.close();
     }
}
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package cn.kuwo;
 
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import cn.kuwo.vo.LoginUserVo;
import cn.kuwo.vo.UserVo;
 
/**
  * 二维码手机端登录
  * @author zijuntang
  *
  */
public class PhoneLoginServlet extends HttpServlet {
     private static final long serialVersionUID = 1L;
     public PhoneLoginServlet() {
         super ();
         // TODO Auto-generated constructor stub
     }
     protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
         doPost(request, response);
     }
     protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
         String uuid = request.getParameter( "uuid" );
         String uname = request.getParameter( "uname" );
         String upwd = request.getParameter( "upwd" );
         System.out.println(uuid);
         System.out.println(uname);
         System.out.println(upwd);
         //TODO 验证登录
         boolean bool = true ;
         if (bool){
             //将登陆信息存入map
             UserVo userVo = LoginUserVo.getLoginUserMap().get(uuid);
             if (userVo == null ){
                 userVo = new UserVo();
                 userVo.setUname(uname);
                 userVo.setUpwd(upwd);
                 LoginUserVo.getLoginUserMap().put(uuid, userVo);
             }
         }
         PrintWriter out = response.getWriter();
         out.print(bool);
         out.flush();
         out.close();
     }
}

cn.kuwo.util包下的生成二维码的封装类

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package cn.kuwo.util; 
   
import java.awt.Color; 
import java.awt.Graphics2D; 
import java.awt.image.BufferedImage; 
import java.io.File; 
import java.io.IOException; 
import java.io.InputStream; 
import java.io.OutputStream; 
import javax.imageio.ImageIO; 
import jp.sourceforge.qrcode.QRCodeDecoder; 
import jp.sourceforge.qrcode.exception.DecodingFailedException; 
import com.swetake.util.Qrcode; 
   
public class TwoDimensionCode { 
       
     /**
      * 生成二维码(QRCode)图片
      * @param content 存储内容
      * @param imgPath 图片路径
      */ 
     public void encoderQRCode(String content, String imgPath) { 
         this .encoderQRCode(content, imgPath, "png" , 7 ); 
    
       
     /**
      * 生成二维码(QRCode)图片
      * @param content 存储内容
      * @param output 输出流
      */ 
     public void encoderQRCode(String content, OutputStream output) { 
         this .encoderQRCode(content, output, "png" , 7 ); 
    
       
     /**
      * 生成二维码(QRCode)图片
      * @param content 存储内容
      * @param imgPath 图片路径
      * @param imgType 图片类型
      */ 
     public void encoderQRCode(String content, String imgPath, String imgType) { 
         this .encoderQRCode(content, imgPath, imgType, 7 ); 
    
       
     /**
      * 生成二维码(QRCode)图片
      * @param content 存储内容
      * @param output 输出流
      * @param imgType 图片类型
      */ 
     public void encoderQRCode(String content, OutputStream output, String imgType) { 
         this .encoderQRCode(content, output, imgType, 7 ); 
    
   
     /**
      * 生成二维码(QRCode)图片
      * @param content 存储内容
      * @param imgPath 图片路径
      * @param imgType 图片类型
      * @param size 二维码尺寸
      */ 
     public void encoderQRCode(String content, String imgPath, String imgType, int size) { 
         try
             BufferedImage bufImg = this .qRCodeCommon(content, imgType, size); 
               
             File imgFile = new File(imgPath);
             if (!imgFile.exists())
             {
                 imgFile.mkdirs();
             }
             // 生成二维码QRCode图片 
             ImageIO.write(bufImg, imgType, imgFile); 
         } catch (Exception e) { 
             e.printStackTrace(); 
        
    
   
     /**
      * 生成二维码(QRCode)图片
      * @param content 存储内容
      * @param output 输出流
      * @param imgType 图片类型
      * @param size 二维码尺寸
      */ 
     public void encoderQRCode(String content, OutputStream output, String imgType, int size) { 
         try
             BufferedImage bufImg = this .qRCodeCommon(content, imgType, size); 
             // 生成二维码QRCode图片 
             ImageIO.write(bufImg, imgType, output); 
         } catch (Exception e) { 
             e.printStackTrace(); 
        
    
       
     /**
      * 生成二维码(QRCode)图片的公共方法
      * @param content 存储内容
      * @param imgType 图片类型
      * @param size 二维码尺寸
      * @return
      */ 
     private BufferedImage qRCodeCommon(String content, String imgType, int size) { 
         BufferedImage bufImg = null
         try
             Qrcode qrcodeHandler = new Qrcode(); 
             // 设置二维码排错率,可选L(7%)、M(15%)、Q(25%)、H(30%),排错率越高可存储的信息越少,但对二维码清晰度的要求越小 
             qrcodeHandler.setQrcodeErrorCorrect( 'M' ); 
             qrcodeHandler.setQrcodeEncodeMode( 'B' ); 
             // 设置设置二维码尺寸,取值范围1-40,值越大尺寸越大,可存储的信息越大 
             qrcodeHandler.setQrcodeVersion(size); 
             // 获得内容的字节数组,设置编码格式 
             byte [] contentBytes = content.getBytes( "utf-8" ); 
             // 图片尺寸 
             int imgSize = 67 + 12 * (size - 1 ); 
             bufImg = new BufferedImage(imgSize, imgSize, BufferedImage.TYPE_INT_RGB); 
             Graphics2D gs = bufImg.createGraphics(); 
             // 设置背景颜色 
             gs.setBackground(Color.WHITE); 
             gs.clearRect( 0 , 0 , imgSize, imgSize); 
   
             // 设定图像颜色> BLACK 
             gs.setColor(Color.BLACK); 
             // 设置偏移量,不设置可能导致解析出错 
             int pixoff = 2
             // 输出内容> 二维码 
             if (contentBytes.length > 0 && contentBytes.length < 800 ) { 
                 boolean [][] codeOut = qrcodeHandler.calQrcode(contentBytes); 
                 for ( int i = 0 ; i < codeOut.length; i++) { 
                     for ( int j = 0 ; j < codeOut.length; j++) { 
                         if (codeOut[j][i]) { 
                             gs.fillRect(j * 3 + pixoff, i * 3 + pixoff, 3 , 3 ); 
                        
                    
                
             } else
                 throw new Exception( "QRCode content bytes length = " + contentBytes.length + " not in [0, 800]." ); 
            
             gs.dispose(); 
             bufImg.flush(); 
         } catch (Exception e) { 
             e.printStackTrace(); 
        
         return bufImg; 
    
       
     /**
      * 解析二维码(QRCode)
      * @param imgPath 图片路径
      * @return
      */ 
     public String decoderQRCode(String imgPath) { 
         // QRCode 二维码图片的文件 
         File imageFile = new File(imgPath); 
         BufferedImage bufImg = null
         String content = null
         try
             bufImg = ImageIO.read(imageFile); 
             QRCodeDecoder decoder = new QRCodeDecoder(); 
             content = new String(decoder.decode( new TwoDimensionCodeImage(bufImg)), "utf-8" );  
         } catch (IOException e) { 
             System.out.println( "Error: " + e.getMessage()); 
             e.printStackTrace(); 
         } catch (DecodingFailedException dfe) { 
             System.out.println( "Error: " + dfe.getMessage()); 
             dfe.printStackTrace(); 
        
         return content; 
    
       
     /**
      * 解析二维码(QRCode)
      * @param input 输入流
      * @return
      */ 
     public String decoderQRCode(InputStream input) { 
         BufferedImage bufImg = null
         String content = null
         try
             bufImg = ImageIO.read(input); 
             QRCodeDecoder decoder = new QRCodeDecoder(); 
             content = new String(decoder.decode( new TwoDimensionCodeImage(bufImg)), "utf-8" );  
         } catch (IOException e) { 
             System.out.println( "Error: " + e.getMessage()); 
             e.printStackTrace(); 
         } catch (DecodingFailedException dfe) { 
             System.out.println( "Error: " + dfe.getMessage()); 
             dfe.printStackTrace(); 
        
         return content; 
    
   
     public static void main(String[] args) { 
         String imgPath = "D:/aaa/Michael_QRCode.png"
         String encoderContent = "http://60.28.201.37:8380/QrCodeLoginPro/Login.html"
         TwoDimensionCode handler = new TwoDimensionCode(); 
         handler.encoderQRCode(encoderContent, imgPath, "png" );
         
         
         /*
         System.out.println("========encoder success"); 
         String decoderContent = handler.decoderQRCode(imgPath); 
         System.out.println("解析结果如下:"); 
         System.out.println(decoderContent); 
         System.out.println("========decoder success!!!"); 
         */
    
}
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package cn.kuwo.util;
   
import java.awt.image.BufferedImage; 
import jp.sourceforge.qrcode.data.QRCodeImage; 
   
public class TwoDimensionCodeImage implements QRCodeImage { 
   
     BufferedImage bufImg; 
       
     public TwoDimensionCodeImage(BufferedImage bufImg) { 
         this .bufImg = bufImg; 
    
       
     @Override 
     public int getHeight() { 
         return bufImg.getHeight(); 
    
   
     @Override 
     public int getPixel( int x, int y) { 
         return bufImg.getRGB(x, y); 
    
   
     @Override 
     public int getWidth() { 
         return bufImg.getWidth(); 
    
   
}

cn.kuwo.vo下的2个数据层

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package cn.kuwo.vo;
 
import java.util.HashMap;
 
public class LoginUserVo {
     private static HashMap<String, UserVo> loginUserMap = new HashMap<String, UserVo>();
     private static LoginUserVo loginUserVo;
     public static LoginUserVo getVo(){
         if (loginUserVo == null ){
             loginUserVo = new LoginUserVo();
         }
         return loginUserVo;
     }
     public static HashMap<String, UserVo> getLoginUserMap() {
         return loginUserMap;
     }
}
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package cn.kuwo.vo;
 
public class UserVo {
     private String uname;
     private String upwd;
     public String getUname() {
         return uname;
     }
     public void setUname(String uname) {
         this .uname = uname;
     }
     public String getUpwd() {
         return upwd;
     }
     public void setUpwd(String upwd) {
         this .upwd = upwd;
     }
}

2个网页

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<!DOCTYPE html>
<html>
<head>
<meta charset= "UTF-8" >
<title>Insert title here</title>
</head>
<script type= "text/javascript" src= "js/jquery-1.11.0.min.js" ></script>
<body>
     <div id= "divCon" >
         <img src= "" id= "QrCodeImg" />
     </div>
</body>
<script type= "text/javascript" >
     $(document).ready(function() {
         var uuid;
         $.get( "/QrCodeLoginPro/GetQrCodeServlet" , function(data, status) {
             var obj = eval( "(" + data + ")" );
             //存储UUID
             uuid = obj.uuid;
             //显示二维码
             $( "#QrCodeImg" ).attr( "src" , obj.qrCodeImg);
             //开始验证登录
             validateLogin();
         });
 
         function validateLogin(){
             $.get( "/QrCodeLoginPro/LongConnectionCheckServlet?uuid=" + uuid , function(data, status) {
                 if (data == "" ){
                     validateLogin();
                 } else {
                     var obj = eval( "(" + data + ")" );
                     alert( "登录成功了:" + obj.uname);
                 }
             });
         }
     });
</script>
</html>
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<!DOCTYPE html>
<html>
<head>
<meta charset= "UTF-8" >
<title>Insert title here</title>
</head>
<style>
.l_m_l {
     float : left;
     font-size: 14px;
     padding: 5px 0 0 0 ;
     width: 330px;
     color: # 414141 ;
}
 
.l_m_linput {
     height: 31px;
     position: relative;
     width: 300px;
     margin-bottom: 21px;
}
 
.l_m_linput span {
     float : left;
     width: 78px;
     text-align: right;
     line-height: 31px;
}
 
input {
     float : left;
     width: 195px;
     height: 24px;
     line-height: 24px;
     background: #f2f2f2;
     border: 1px solid #c4c4c4;
     padding: 2px 22px 2px 2px;
}
 
.l_mimacon {
     position: absolute;
     top: 6px;
     right: 6px;
     width: 15px;
     height: 17px;
     background: url(img/l_mimacon.png)
         no-repeat;
}
 
.l_peoplecon {
     position: absolute;
     top: 7px;
     right: 6px;
     width: 15px;
     height: 15px;
     background: url(img/l_peoplecon.png)
         no-repeat;
}
 
.l_m_lload a {
     display: block;
     width: 154px;
     height: 40px;
     background:
         url(img/l_loadingbtn.png)
         no-repeat;
     margin: 0 auto;
     line-height: 40px;
     text-align: center;
     font-size: 18px;
     color: #52340c;
     text-decoration: none;
}
</style>
<script type= "text/javascript" src= "js/jquery-1.11.0.min.js" ></script>
<body style= " border-top-right-radius: 0px !important; border-bottom-right-radius: 0px !important; border-bottom-left-radius: 0px !important; background-image: none !important; border: 0px !important; bottom: auto !important; float: none !important; height: auto !important; left: auto !important; line-height: 1.1em !important; margin: 0px !important; outline: 0px !important; overflow: visible !important; padding: 0px !important; position: static !important; right: auto !important; top: auto !important; vertical-align: baseline !important; width: auto !important; box-sizing: content-box !important; font-family: Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace !important; font-size: 1em !important; min-height: inherit !important;">>
     <div style= "margin-left: 100px;" ><img src= "img/logo.png" /></div>
     <div >
         <p class = "l_m_linput" >
             <span><font color= "#fff" >用户名:</font></span><input type= "text" id= "login_name" value= "zijuntang" ><em
                 class = "l_peoplecon" ></em>
         </p>
         <p class = "l_m_linput" >
             <span><font color= "#fff" >密码:</font></span><input type= "password" id= "login_psw" value= "tangzijun" ><em
                 class = "l_mimacon" ></em>
         </p>
         <div class = "l_m_linput2" ></div>
         <div class = "l_m_lload" >
             <a href= "javascript:login();" >登录</a>
         </div>
     </div>
</body>
<script type= "text/javascript" >
     //登录
     function login(){
         $.post( "/QrCodeLoginPro/PhoneLoginServlet" , {
             uuid : $.getUrlParam( 'uuid' ),
             uname:$( "#login_name" ).val(),
             upwd:$( "#login_psw" ).val()
         }, function(data, status) {
             if (data == "" ){
                 alert( "登录失败" );
             } else {
                 alert( "登录成功" );
             }
         });
     }
     
     //获取网页参数
     (function($){
         $.getUrlParam = function(name){
             var reg = new RegExp( "(^|&)" + name + "=([^&]*)(&|$)" );
             var r = window.location.search.substr( 1 ).match(reg);
             if (r!= null ) return unescape(r[ 2 ]); return null ;
         }
         })(jQuery);
</script>
</html>

web.xml配置文件

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<?xml version= "1.0" encoding= "UTF-8" ?>
     id= "WebApp_ID" version= "2.5" >
     <display-name>QrCodeLoginPro</display-name>
     <welcome-file-list>
         <welcome-file>index.html</welcome-file>
     </welcome-file-list>
     <servlet>
         <description></description>
         <display-name>长连接检查登录状态</display-name>
         <servlet-name>LongConnectionCheckServlet</servlet-name>
         <servlet- class >cn.kuwo.LongConnectionCheckServlet</servlet- class >
     </servlet>
     <servlet-mapping>
         <servlet-name>LongConnectionCheckServlet</servlet-name>
         <url-pattern>/LongConnectionCheckServlet</url-pattern>
     </servlet-mapping>
 
     <servlet>
         <description>获取二维码图片以及uuid</description>
         <display-name>GetQrCodeServlet</display-name>
         <servlet-name>GetQrCodeServlet</servlet-name>
         <servlet- class >cn.kuwo.GetQrCodeServlet</servlet- class >
     </servlet>
     <servlet-mapping>
         <servlet-name>GetQrCodeServlet</servlet-name>
         <url-pattern>/GetQrCodeServlet</url-pattern>
     </servlet-mapping>
 
     <servlet>
         <description>手机扫描二维码之后进行登录</description>
         <display-name>PhoneLoginServlet</display-name>
         <servlet-name>PhoneLoginServlet</servlet-name>
         <servlet- class >cn.kuwo.PhoneLoginServlet</servlet- class >
     </servlet>
     <servlet-mapping>
         <servlet-name>PhoneLoginServlet</servlet-name>
         <url-pattern>/PhoneLoginServlet</url-pattern>
     </servlet-mapping>
</web-app>

此外还需要1个二维码开源包:QRCode.jar

源码下载:http://files.cnblogs.com/zijun/%E4%BA%8C%E7%BB%B4%E7%A0%81%E7%99%BB%E5%BD%95%E4%BE%8B%E5%AD%90.rar

转载于:https://www.cnblogs.com/nearpengju123/p/5185784.html

版权声明:本文为博主原创文章,遵循 CC 4.0 BY-SA 版权协议,转载请附上原文出处链接和本声明。
本文链接:https://blog.csdn.net/weixin_30624825/article/details/99535120

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