Java获取随机的流水号(10位)

/**
     * 获取随机的流水号(10位)
     * @return
     */
     public static String getRandomReqNo() {
          int length=10;
         String base = "abcdefghijklmnopqrstuvwxyz0123456789";
         Random random = new Random();
         StringBuffer sb = new StringBuffer();
         for (int i = 0; i < length; i++) {
             int number = random.nextInt(base.length());
             sb.append(base.charAt(number));
         }
         return sb.toString();
     }