Java生成随机密码详解编程语言

public class RandomString { 
 
          public static String randomstring(int lo, int hi){ 
                  int n = rand(lo, hi); 
                  byte b[] = new byte[n]; 
                  for (int i = 0; i < n; i++) 
                          b[i] = (byte)rand('a', 'z'); 
                  return new String(b, 0); 
          } 
 
          private static int rand(int lo, int hi){ 
                      java.util.Random rn = new java.util.Random(); 
                  int n = hi - lo + 1; 
                  int i = rn.nextInt(n); 
                  if (i < 0) 
                          i = -i; 
                  return lo + i; 
          } 
 
          public static String randomstring(){ 
                  return randomstring(5, 25); 
          } 
 
        /** 
         * @param args 
         */ 
        public static void main(String[] args) { 
                System.out.println(randomstring()); 
 
        } 
 
}