jQuery+Struts2無刷新驗證碼

1.產生圖片的工廠:

1. package org.blog.util;
4. import java.awt.Color;
5. import java.awt.Font;
6. import java.awt.Graphics;
7. import java.awt.image.BufferedImage;
8. import java.io.ByteArrayInputStream;
9. import java.io.ByteArrayOutputStream;
10. import java.util.Random;
13. import javax.imageio.ImageIO;
14. import javax.imageio.stream.ImageOutputStream;
19. public class RandomNumUtil
20. {
21. private ByteArrayInputStream image;
22. private String str;
24. public RandomNumUtil()
25. {
26. init();
27. }
29. public static RandomNumUtil Instance()
30. {
31. return new RandomNumUtil();
32. }
34. public ByteArrayInputStream getImage()
35. {
36. return this.image;
37. }
39. public String getString()
40. {
41. return this.str;
42. }
44. private void init()
45. {
46. //在內存中創建圖象
47. int width = 109;
48. int height = 40;
49. BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
51. /* 獲取內在中圖像的上下文 */
52. Graphics g = image.getGraphics();
54. /* 創建一個隨機類 */
55. Random random = new Random();
57. /* 設置背景顏色 */
58. g.setColor(this.getRandColor(200, 250));
59. g.fillRect(0, 0, width, height);
61. /* 設置字體 */
62. g.setFont(new Font("Times New Roman", Font.PLAIN, 28));
64. /* 設置干擾線的顏色 */
65. g.setColor(getRandColor(160, 200));
66. for (int i=0; i<155; i++)
67. {
68. int x = random.nextInt(width);
69. int y = random.nextInt(height);
70. int xl = random.nextInt(12);
71. int yl = random.nextInt(12);
72. g.drawLine(x, y, x+xl, y+yl);
73. }
75. /* 用來臨時保存隨機產生的數字 */
76. String sRand = "";
77. for (int i=0; i<4; i++)
78. {
79. String rand = String.valueOf(random.nextInt(10));
80. sRand += rand;
81. g.setColor(new Color(20 + random.nextInt(110), 20+random.nextInt(110), 20+random.nextInt(110) ));
82. g.drawString(rand, 20*i+10, 25);
83. /* 然後賦給str */
84. this.str = sRand;
85. }
86. /* 使圖像生效 */
87. g.dispose();
90. ByteArrayInputStream input = null;
91. ByteArrayOutputStream output = new ByteArrayOutputStream();
92. try
93. {
94. ImageOutputStream imageOutput = ImageIO.createImageOutputStream(output);
95. ImageIO.write(image, "JPEG", imageOutput);
96. imageOutput.close();
97. input = new ByteArrayInputStream(output.toByteArray());
98. } catch (Exception e)
99. {
100. System.out.println("驗證碼圖片產生出現錯誤："+e.toString());
101. }
102. this.image = input;
103. }
105. /* 隨機產生顏色 */
106. private Color getRandColor(int fc, int bc)
107. {
108. Random random = new Random();
109. if (fc > 255)
110. fc = 255;
111. if (bc > 255)
112. bc = 255;
113. int r = fc + random.nextInt(bc - fc);
114. int g = fc + random.nextInt(bc - fc);
115. int b = fc + random.nextInt(bc - fc);
116. return new Color(r, g, b);
117. }
118. }

2.通過Action獲取該圖片:

1. package org.blog.admin.action;
4. import java.io.ByteArrayInputStream;
7. import org.blog.util.RandomNumUtil;
10. import com.opensymphony.xwork2.ActionContext;
11. import com.opensymphony.xwork2.ActionSupport;
14. public class GetRandomNum extends ActionSupport
15. {
16. private static final long serialVersionUID = 1L;
17. private ByteArrayInputStream inputStream;
19. public ByteArrayInputStream getInputStream()
20. {
21. return inputStream;
22. }
25. public void setInputStream(ByteArrayInputStream inputStream)
26. {
27. this.inputStream = inputStream;
28. }
31. public String execute() throws Exception
32. {
33. RandomNumUtil randomNumUtil = RandomNumUtil.Instance();
34. this.setInputStream(randomNumUtil.getImage());
35. ActionContext.getContext().getSession().put("validateCode", randomNumUtil.getString());
36. return SUCCESS;
37. }
38. }

3.在strus.xml中配置:

1. <!-- 獲取隨機產生的數字驗證碼 -->
2. <action name="getRandomNumber" class="org.blog.admin.action.GetRandomNum">
3. <result type="stream">
4. <param name="contentType">image/jpeg</param>
5. <param name="inputName">inputStream</param>
6. </result>
7. </action>

4.在jsp文件中:

1. <img src="getRandomNumber" width="90" height="25" alt="驗證碼圖片" id="randomCode"/>
2. <a href="#" id="refresh" style="font-size:12px;">看不楚，換張圖片</a>

5.局部刷新驗證碼的js代碼:(主要的思想是讓圖片的src屬性,通過js來每次重新加載一次action.可以通過產生隨機數或以當前時間為種子,這樣每次都去重新讀取產生圖片的Action了)

1. $(function() {
2. $("#refresh").click(function() {
3. var rom = new Date();
4. $("#randomCode").attr("src", "getRandomNumber?timestamp="+rom);
5. });
6. });