验证码产生程序

登录的时候,经常需要输入验证码,我们来写一个验证码产生的函数,包括数字,大写字母,小写字母各种情况的组合

VerifyCode.java

  1 package com.xiejiaohui.util;
  2 
  3 import java.util.Random;
  4 
  5 /**
  6  * 验证码产生器  2016-01-24
  7  * 
  8  * @author xiejiaohui
  9  *
 10  */
 11 public class VerifyCode {
 12 
 13     /**
 14      * 产生验证码
 15      * 
 16      * @param type
 17      * @param length
 18      * @param exChars
 19      * @return
 20      */
 21     public static String generateTextCode(int type, int length, String exChars) {
 22         if (length <= 0) {
 23             return "";
 24         }
 25         StringBuffer code = new StringBuffer();
 26         int i = 0;
 27         Random r = new Random();
 28         switch (type) {
 29         default:
 30             break;
 31         case 0: // 仅数字
 32             while (i < length) {
 33                 int t = r.nextInt(10);
 34                 if (exChars == null || exChars.indexOf((new StringBuilder(String.valueOf(t))).toString()) < 0) {
 35                     code.append(t);
 36                     i++;
 37                 }
 38             }
 39             break;
 40         case 1: // 仅字母(即大写字母、小写字母混合)
 41             while (i < length) {
 42                 int t = r.nextInt(123);
 43                 if ((t >= 97 || t >= 65 && t <= 90) && (exChars == null || exChars.indexOf((char) t) < 0)) {
 44                     code.append((char) t);
 45                     i++;
 46                 }
 47             }
 48             break;
 49         case 2: // 数字、大写字母、小写字母混合
 50             while (i < length) {
 51                 int t = r.nextInt(123);
 52                 if ((t >= 97 || t >= 65 && t <= 90 || t >= 48 && t <= 57)
 53                         && (exChars == null || exChars.indexOf((char) t) < 0)) {
 54                     code.append((char) t);
 55                     i++;
 56                 }
 57             }
 58             break;
 59         case 3: // 数字、大写字母混合
 60             while (i < length) {
 61                 int t = r.nextInt(91);
 62                 if ((t >= 65 || t >= 48 && t <= 57) && (exChars == null || exChars.indexOf((char) t) < 0)) {
 63                     code.append((char) t);
 64                     i++;
 65                 }
 66             }
 67             break;
 68         case 4: // 数字、小写字母混合
 69             while (i < length) {
 70                 int t = r.nextInt(123);
 71                 if ((t >= 97 || t >= 48 && t <= 57) && (exChars == null || exChars.indexOf((char) t) < 0)) {
 72                     code.append((char) t);
 73                     i++;
 74                 }
 75             }
 76             break;
 77         case 5: // 仅大写字母
 78             while (i < length) {
 79                 int t = r.nextInt(91);
 80                 if (t >= 65 && (exChars == null || exChars.indexOf((char) t) < 0)) {
 81                     code.append((char) t);
 82                     i++;
 83                 }
 84             }
 85             break;
 86         case 6: // 仅小写字母
 87             while (i < length) {
 88                 int t = r.nextInt(123);
 89                 if (t >= 97 && (exChars == null || exChars.indexOf((char) t) < 0)) {
 90                     code.append((char) t);
 91                     i++;
 92                 }
 93             }
 94             break;
 95         }
 96         return code.toString();
 97     }
 98 
 99     public static void main(String[] args) {
100         // 10以内的随机数: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9    不包括10
101         Random random = new Random();
102         System.out.println(random.nextInt(10));
103         
104         // 大写字母
105         for(int i = 65; i <= 90; i++) {
106             System.out.print((char)i);
107             System.out.print(" ");
108         }
109         System.out.println();
110 
111         // 小写字母
112         for(int i = 97; i <= 122; i++) {
113             System.out.print((char)i);
114             System.out.print(" ");
115         }
116         System.out.println();
117         
118         // 数字
119         for(int i = 48; i <= 57; i++) {
120             System.out.print((char)i);
121             System.out.print(" ");
122         }
123         System.out.println();
124 
125         System.out.println(VerifyCode.generateTextCode(0, 32, "0")); // 数字
126         System.out.println(VerifyCode.generateTextCode(1, 32, "l")); // 大写字母和小写字母组合
127         System.out.println(VerifyCode.generateTextCode(2, 32, "l")); // 数字大写字母、小写字母组合
128         System.out.println(VerifyCode.generateTextCode(3, 32, "0")); // 数字和大写字母组合
129         System.out.println(VerifyCode.generateTextCode(4, 32, "0")); // 数字和小写字母组合
130         System.out.println(VerifyCode.generateTextCode(5, 32, "Z")); // 大写字母
131         System.out.println(VerifyCode.generateTextCode(6, 32, "o")); // 小写字母
132         
133     }
134 
135 }

输出:

 1 5
 2 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z 
 3 a b c d e f g h i j k l m n o p q r s t u v w x y z 
 4 0 1 2 3 4 5 6 7 8 9 
 5 62651637842124942893714462981794
 6 YMFcVREgxazamXFoAgkjKJimFohafisJ
 7 sZecd9cNP9hufE3ZrQIVxEKtR6tkUkVj
 8 3MJUZ6JD1QZSC4RNR6C4VC6YT4DWHHBY
 9 pdqdwia9csl8e89xneh1lvvnrh2btkdz
10 HMTFHCGUXVABGIVSLRCWAGQDABYKQVDB
11 uwikqkqaeiemvphctmyhxctdsfwrkkgh

 

posted @ 2016-01-24 20:06  Josh_Xie  阅读(253)  评论(0编辑  收藏  举报