/** * 生成随机数字 * @param length * @return */ protected String randomNum(int length) { StringBuffer buffer = null; StringBuffer sb = new StringBuffer(); Random r = new Random(); r.setSeed(new Date().getTime()); buffer = new StringBuffer("0123456789"); int range = buffer.length(); for (int i = 0; i < length; ++i) { sb.append(buffer.charAt(r.nextInt(range))); } return sb.toString(); }