随机生成n位字母加数字字符长

?

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22

public static String getRandomString(int n) {           String val = "";         Random random = new Random();           // 参数length，表示生成几位随机数         for (int i = 0; i < n; i++) {             // 随机数由0-9，a-z,A-Z组成，数字占10个，字母占52个，数字、字母占比1:5（标准的应该是10:52）             // random.nextInt(6) 0-5中6个数取一个             String charOrNum = (random.nextInt(6) + 6) % 6 >= 1 ? "char" : "num";             // 输出字母还是数字             if ("char".equalsIgnoreCase(charOrNum)) {                 // 输出是大写字母还是小写字母，输出比例为1:1                 int temp = random.nextInt(2) % 2 == 0 ? 97 : 65;                 // char（65）-char(90) 为大写字母A-Z；char(97)-char(122)为小写字母a-z                 val += (char) (random.nextInt(26) + temp);             } else if ("num".equalsIgnoreCase(charOrNum)) {                 val += String.valueOf(random.nextInt(10));             }         }         return val;     }