JAva検証コード(struts 2で実現)回転

ステップ1:認証コードのアクションの作成

 1 package com;

 2 

 3 import java.awt.Color;

 4 import java.awt.Font;

 5 import java.awt.Graphics;

 6 import java.awt.image.BufferedImage;

 7 import java.util.Random;

 8 

 9 import javax.imageio.ImageIO;

10 import javax.servlet.ServletOutputStream;

11 import javax.servlet.http.HttpServletRequest;

12 import javax.servlet.http.HttpServletResponse;

13 import javax.servlet.http.HttpSession;

14 

15 import org.apache.commons.lang.RandomStringUtils;

16 import org.apache.struts2.ServletActionContext;

17 public class AuthCodeAction {

18     private HttpServletResponse response = ServletActionContext.getResponse();

19     private HttpServletRequest request = ServletActionContext.getRequest();

20 

21     public String execute() {

22         try {

23             int width = 50;

24             int height = 18;

25             //     4          

26             String s = RandomStringUtils.random(4, true, true);

27 

28             //    session,            .

29             //          session.

30             HttpSession session = request.getSession(true);

31             session.setAttribute("authCode", s);

32 

33             response.setContentType("images/jpeg");

34             response.setHeader("Pragma", "No-cache");

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

36             response.setDateHeader("Expires", 0);

37 

38             ServletOutputStream out = response.getOutputStream();

39             BufferedImage image = new BufferedImage(width, height,

40                     BufferedImage.TYPE_INT_RGB);

41             Graphics g = image.getGraphics();

42             //      

43             g.setColor(getRandColor(200, 250));

44             g.fillRect(0, 0, width, height);

45 

46             //     

47             Font mFont = new Font("Times New Roman", Font.BOLD, 18);//     

48             g.setFont(mFont);

49 

50             //    

51             // g.setColor(Color.BLACK);

52             // g.drawRect(0, 0, width - 1, height - 1);

53 

54             //        ，                  

55             g.setColor(getRandColor(160, 200));

56             //      

57             Random random = new Random();

58             for (int i = 0; i < 155; i++) {

59                 int x2 = random.nextInt(width);

60                 int y2 = random.nextInt(height);

61                 int x3 = random.nextInt(12);

62                 int y3 = random.nextInt(12);

63                 g.drawLine(x2, y2, x2 + x3, y2 + y3);

64             }

65 

66             //           

67             g.setColor(new Color(20 + random.nextInt(110), 20 + random

68                     .nextInt(110), 20 + random.nextInt(110)));

69 

70             g.drawString(s, 2, 16);

71 

72             //     

73             g.dispose();

74             //        

75             ImageIO.write((BufferedImage) image, "JPEG", out);

76             out.close();

77         } catch (Exception e) {

78             e.printStackTrace();

79         }

80         return null;

81     }

82 

83     private Color getRandColor(int fc, int bc) { //           

84         Random random = new Random();

85         if (fc > 255)

86             fc = 255;

87         if (bc > 255)

88             bc = 255;

89         int r = fc + random.nextInt(bc - fc);

90         int g = fc + random.nextInt(bc - fc);

91         int b = fc + random.nextInt(bc - fc);

92         return new Color(r, g, b);

93     }

94 }

ステップ2:actionの構成

<span style="font-size:18px;"><?xml version="1.0" encoding="UTF-8" ?>

<!DOCTYPE struts PUBLIC "-//Apache Software Foundation//DTD Struts Configuration 2.1//EN" "http://struts.apache.org/dtds/struts-2.1.dtd">

<struts>

    <package name="test" namespace="/test" extends="struts-default">

        <action name="authCode" class="com.AuthCodeAction" method="execute">

        </action>

    </package>

</struts>

ステップ3:jspページの作成(jqueryによる動的リフレッシュ)
 

<%@ page language="java" import="java.util.*" pageEncoding="GB18030"%>

<%

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>   </title>

    <script type="text/javascript" src="js/jquery-1.6.2.min.js">

    </script>

    <script type="text/javascript">

    function changeImg(){     

        $("#authCode").attr("src","test/authCode.action?d="+new Date().valueOf());     

    }    

    </script>

  </head>

  

  <body>

  <center>

           <br>

           <img src="test/authCode.action" alt="   " id="authCode" onclick="changeImg()"> 

          <a href="#" onclick="changeImg()">   ，   ！</a> 

  </center>

  </body>

</html>