最近做驗證碼，參考網上案例，發現有不少問題，特意進行了修改和完善。

驗證碼生成器：

1. import javax.imageio.ImageIO;
2. import java.awt.*;
3. import java.awt.image.BufferedImage;
4. import java.io.FileOutputStream;
5. import java.io.IOException;
6. import java.io.OutputStream;
7. import java.util.Date;
8. import java.util.Random;
10. /**
11. * 驗證碼生成器
12. *
13. * @author
14. */
15. public class ValidateCode {
16. // 圖片的寬度。
17. private int width = 160;
18. // 圖片的高度。
19. private int height = 40;
20. // 驗證碼字符個數
21. private int codeCount = 5;
22. // 驗證碼幹擾線數
23. private int lineCount
    = 150;
24. // 驗證碼
25. private String code = null;
26. // 驗證碼圖片Buffer
27. private BufferedImage buffImg = null;
29. // 驗證碼範圍,去掉0(數字)和O(拼音)容易混淆的(小寫的1和L也可以去掉,大寫不用了)
30. private char[] codeSequence = {‘A‘, ‘B‘, ‘C‘, ‘D‘, ‘E‘, ‘F‘, ‘G‘, ‘H‘, ‘I‘, ‘J‘,
31. ‘K‘, ‘L‘, ‘M‘, ‘N‘, ‘P‘, ‘Q‘, ‘R‘, ‘S‘, ‘T‘, ‘U‘, ‘V‘, ‘W‘,
32. ‘X‘, ‘Y‘, ‘Z‘, ‘1‘, ‘2‘, ‘3‘, ‘4‘, ‘5‘, ‘6‘, ‘7‘, ‘8‘, ‘9‘};
34. /**
35. * 默認構造函數,設置默認參數
36. */
37. public ValidateCode() {
38. this.createCode();
39. }
41. /**
42. * @param width 圖片寬
43. * @param height 圖片高
44. */
45. public ValidateCode(int width, int height) {
46. this.width = width;
47. this.height = height;
48. this.createCode();
49. }
51. /**
52. * @param width 圖片寬
53. * @param height 圖片高
54. * @param codeCount 字符個數
55. * @param lineCount 幹擾線條數
56. */
57. public ValidateCode(int width, int height, int codeCount, int lineCount) {
58. this.width = width;
59. this.height = height;
60. this.codeCount = codeCount;
61. this.lineCount = lineCount;
62. this.createCode();
63. }
65. public void createCode() {
66. int x = 0, fontHeight = 0, codeY = 0;
67. int red = 0, green = 0, blue = 0;
69. x = width / (codeCount + 2);//每個字符的寬度(左右各空出一個字符)
70. fontHeight = height - 2;//字體的高度
71. codeY = height - 4;
73. // 圖像buffer
74. buffImg = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
75. Graphics2D g = buffImg.createGraphics();
76. // 生成隨機數
77. Random random = new Random();
78. // 將圖像填充為白色
79. g.setColor(Color.WHITE);
80. g.fillRect(0, 0, width, height);
81. // 創建字體,可以修改為其它的
82. Font font = new Font("Fixedsys", Font.PLAIN, fontHeight);
83. // Font font = new Font("Times New Roman", Font.ROMAN_BASELINE, fontHeight);
84. g.setFont(font);
86. for (int i = 0; i < lineCount; i++) {
87. // 設置隨機開始和結束坐標
88. int xs = random.nextInt(width);//x坐標開始
89. int ys = random.nextInt(height);//y坐標開始
90. int xe = xs + random.nextInt(width / 8);//x坐標結束
91. int ye = ys + random.nextInt(height / 8);//y坐標結束
93. // 產生隨機的顏色值，讓輸出的每個幹擾線的顏色值都將不同。
94. red = random.nextInt(255);
95. green = random.nextInt(255);
96. blue = random.nextInt(255);
97. g.setColor(new Color(red, green, blue));
98. g.drawLine(xs, ys, xe, ye);
99. }
101. // randomCode記錄隨機產生的驗證碼
102. StringBuffer randomCode = new StringBuffer();
103. // 隨機產生codeCount個字符的驗證碼。
104. for (int i = 0; i < codeCount; i++) {
105. String strRand = String.valueOf(codeSequence[random.nextInt(codeSequence.length)]);
106. // 產生隨機的顏色值，讓輸出的每個字符的顏色值都將不同。
107. red = random.nextInt(255);
108. green = random.nextInt(255);
109. blue = random.nextInt(255);
110. g.setColor(new Color(red, green, blue));
111. g.drawString(strRand, (i + 1) * x, codeY);
112. // 將產生的四個隨機數組合在一起。
113. randomCode.append(strRand);
114. }
115. // 將四位數字的驗證碼保存到Session中。
116. code = randomCode.toString();
117. }
119. public void write(String path) throws IOException {
120. OutputStream sos = new FileOutputStream(path);
121. this.write(sos);
122. }
124. public void write(OutputStream sos) throws IOException {
125. ImageIO.write(buffImg, "png", sos);
126. sos.close();
127. }
129. public BufferedImage getBuffImg() {
130. return buffImg;
131. }
133. public String getCode() {
134. return code;
135. }
137. /**
138. * 測試函數,默認生成到d盤
139. * @param args
140. */
141. public static void main(String[] args) {
142. ValidateCode vCode = new ValidateCode(160,40,5,150);
143. try {
144. String path="D:/"+new Date().getTime()+".png";
145. System.out.println(vCode.getCode()+" >"+path);
146. vCode.write(path);
147. } catch (IOException e) {
148. e.printStackTrace();
149. }
150. }
151. }

import javax.imageio.ImageIO;  import java.awt.*;  import java.awt.image.BufferedImage;  import java.io.FileOutputStream;  import java.io.IOException;  import java.io.OutputStream;  import java.util.Date;  import java.util.Random;    /**  * 驗證碼生成器  *  * @author   */  public class ValidateCode {      // 圖片的寬度。      private int width = 160;      // 圖片的高度。      private int height = 40;      // 驗證碼字符個數      private int codeCount = 5;      // 驗證碼幹擾線數      private int lineCount = 150;      // 驗證碼      private String code = null;      // 驗證碼圖片Buffer      private BufferedImage buffImg = null;        // 驗證碼範圍,去掉0(數字)和O(拼音)容易混淆的(小寫的1和L也可以去掉,大寫不用了)      private char[] codeSequence = {‘A‘, ‘B‘, ‘C‘, ‘D‘, ‘E‘, ‘F‘, ‘G‘, ‘H‘, ‘I‘, ‘J‘,              ‘K‘, ‘L‘, ‘M‘, ‘N‘, ‘P‘, ‘Q‘, ‘R‘, ‘S‘, ‘T‘, ‘U‘, ‘V‘, ‘W‘,              ‘X‘, ‘Y‘, ‘Z‘, ‘1‘, ‘2‘, ‘3‘, ‘4‘, ‘5‘, ‘6‘, ‘7‘, ‘8‘, ‘9‘};        /**      * 默認構造函數,設置默認參數      */      public ValidateCode() {          this.createCode();      }        /**      * @param width  圖片寬      * @param height 圖片高      */      public ValidateCode(int width, int height) {          this.width = width;          this.height = height;          this.createCode();      }        /**      * @param width     圖片寬      * @param height    圖片高      * @param codeCount 字符個數      * @param lineCount 幹擾線條數      */      public ValidateCode(int width, int height, int codeCount, int lineCount) {          this.width = width;          this.height = height;          this.codeCount = codeCount;          this.lineCount = lineCount;          this.createCode();      }        public void createCode() {          int x = 0, fontHeight = 0, codeY = 0;          int red = 0, green = 0, blue = 0;            x = width / (codeCount + 2);//每個字符的寬度(左右各空出一個字符)          fontHeight = height - 2;//字體的高度          codeY = height - 4;            // 圖像buffer          buffImg = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);          Graphics2D g = buffImg.createGraphics();          // 生成隨機數          Random random = new Random();          // 將圖像填充為白色          g.setColor(Color.WHITE);          g.fillRect(0, 0, width, height);          // 創建字體,可以修改為其它的          Font font = new Font("Fixedsys", Font.PLAIN, fontHeight);  //        Font font = new Font("Times New Roman", Font.ROMAN_BASELINE, fontHeight);          g.setFont(font);            for (int i = 0; i < lineCount; i++) {              // 設置隨機開始和結束坐標              int xs = random.nextInt(width);//x坐標開始              int ys = random.nextInt(height);//y坐標開始              int xe = xs + random.nextInt(width / 8);//x坐標結束              int ye = ys + random.nextInt(height / 8);//y坐標結束                // 產生隨機的顏色值，讓輸出的每個幹擾線的顏色值都將不同。              red = random.nextInt(255);              green = random.nextInt(255);              blue = random.nextInt(255);              g.setColor(new Color(red, green, blue));              g.drawLine(xs, ys, xe, ye);          }            // randomCode記錄隨機產生的驗證碼          StringBuffer randomCode = new StringBuffer();          // 隨機產生codeCount個字符的驗證碼。          for (int i = 0; i < codeCount; i++) {              String strRand = String.valueOf(codeSequence[random.nextInt(codeSequence.length)]);              // 產生隨機的顏色值，讓輸出的每個字符的顏色值都將不同。              red = random.nextInt(255);              green = random.nextInt(255);              blue = random.nextInt(255);              g.setColor(new Color(red, green, blue));              g.drawString(strRand, (i + 1) * x, codeY);              // 將產生的四個隨機數組合在一起。              randomCode.append(strRand);          }          // 將四位數字的驗證碼保存到Session中。          code = randomCode.toString();      }        public void write(String path) throws IOException {          OutputStream sos = new FileOutputStream(path);          this.write(sos);      }        public void write(OutputStream sos) throws IOException {          ImageIO.write(buffImg, "png", sos);          sos.close();      }        public BufferedImage getBuffImg() {          return buffImg;      }        public String getCode() {          return code;      }        /**      * 測試函數,默認生成到d盤      * @param args      */      public static void main(String[] args) {          ValidateCode vCode = new ValidateCode(160,40,5,150);          try {              String path="D:/"+new Date().getTime()+".png";              System.out.println(vCode.getCode()+" >"+path);              vCode.write(path);          } catch (IOException e) {              e.printStackTrace();          }      }  }  

1. // 刷新圖片
2. function changeImg() {
3. var imgSrc = $("#imgObj");
4. var url = imgSrc.attr("src");
5. imgSrc.attr("src", changeUrl(url));
6. }
7. //為了使每次生成圖片不一致，即不讓瀏覽器讀緩存，所以需要加上時間戳
8. function changeUrl(url) {
9. var timestamp = (new Date()).valueOf();
10. var index = url.indexOf("?");
11. console.log(index);
12. if (index > 0) {
13. url = url.substring(0, url.indexOf("?"));
14. }
15. console.log(url);
16. if ((url.indexOf("&") > 0)) {
17. url = url + "×tamp=" + timestamp;
18. console.log(url);
19. } else {
20. url = url + "?timestamp=" + timestamp;
21. console.log(url);
22. }
23. return url;
24. }

 // 刷新圖片              function changeImg() {                  var imgSrc = $("#imgObj");                  var url = imgSrc.attr("src");                 imgSrc.attr("src", changeUrl(url));              }              //為了使每次生成圖片不一致，即不讓瀏覽器讀緩存，所以需要加上時間戳              function changeUrl(url) {                  var timestamp = (new Date()).valueOf();                  var index = url.indexOf("?");                console.log(index);                 if (index > 0) {                      url = url.substring(0, url.indexOf("?"));                  }                console.log(url);                if ((url.indexOf("&") > 0)) {                      url = url + "×tamp=" + timestamp;                      console.log(url);                } else {                      url = url + "?timestamp=" + timestamp;                    console.log(url);                }                  return url;              }

1. /**
2. * 響應驗證碼頁面
3. * @return
4. */
5. @RequestMapping(value="/validateCode")
6. public String validateCode(HttpServletRequest request,HttpServletResponse response) throws Exception{
7. // 設置響應的類型格式為圖片格式
8. response.setContentType("image/jpeg");
9. //禁止圖像緩存。
10. response.setHeader("Pragma", "no-cache");
11. response.setHeader("Cache-Control", "no-cache");
12. response.setDateHeader("Expires", 0);
14. HttpSession session = request.getSession();
16. ValidateCode vCode = new ValidateCode(120,40,5,100);
17. session.setAttribute("code", vCode.getCode());
18. vCode.write(response.getOutputStream());
19. return null;
20. }

/**  * 響應驗證碼頁面  * @return  */  @RequestMapping(value="/validateCode")  public String validateCode(HttpServletRequest request,HttpServletResponse response) throws Exception{      // 設置響應的類型格式為圖片格式      response.setContentType("image/jpeg");      //禁止圖像緩存。      response.setHeader("Pragma", "no-cache");      response.setHeader("Cache-Control", "no-cache");      response.setDateHeader("Expires", 0);        HttpSession session = request.getSession();        ValidateCode vCode = new ValidateCode(120,40,5,100);      session.setAttribute("code", vCode.getCode());      vCode.write(response.getOutputStream());      return null;  }  

1. String code = request.getParameter("code");
2. HttpSession session = request.getSession();
3. String sessionCode = (String) session.getAttribute("code");
4. if (!StringUtils.equalsIgnoreCase(code, sessionCode)) { //忽略驗證碼大小寫
5. throw new RuntimeException("驗證碼對應不上code=" + code + " sessionCode=" + sessionCode);
6. }

String code = request.getParameter("code");  HttpSession session = request.getSession();  String sessionCode = (String) session.getAttribute("code");  if (!StringUtils.equalsIgnoreCase(code, sessionCode)) {  //忽略驗證碼大小寫      throw new RuntimeException("驗證碼對應不上code=" + code + "  sessionCode=" + sessionCode);  } 

java圖形驗證碼生成工具類及web頁面校驗驗證碼