啊啊啊

 1 public class TestRandom {
 2     public static void main(String[] args) {
 3         System.out.println(getRandomCharacter(‘0‘, ‘9‘));
 4         System.out.println(getRandomCharacter(‘a‘, ‘z‘));
 5         System.out.println(getRandomCharacter(‘A‘, ‘Z‘));
 6         System.out.println(getRandomCharacter(‘\u0000‘, ‘\uFFFF‘));
 7     }
 8     
 9     /**
10      * 每一个字符都有唯一的统一码；在0到十六进制FFFF（即十进制65535）之间。
11      * */
12     public static char getRandomCharacter(char ch1, char ch2) {
13         return (char)(ch1 + Math.random() * (ch2 - ch1 + 1));
14     }
15 }