/**     * 生成订单编号：站点编号前三位 + [5,12]位自增编号     *      * @param siteCode     * @return     * @author jqlin     */    private String getOrderNo(String siteCode) {        String result = siteCode.length() <= 3 ? siteCode : siteCode.substring(0, 3);        result = result.toUpperCase();        try {            String orderNoIncr = "orderNoIncr";            if(!RedisUtil.exists(orderNoIncr)) {                RedisUtil.set(orderNoIncr, "0");            }                        //根据redis生成自增ID            Long seq = RedisUtil.incr(orderNoIncr);            if(seq == null || seq == 0L) {                //根据mysql生成自增ID                seq = (Long)idDao.save(new IdModel());                result = result + "DB" + Util.getSequence(seq);            } else {                result = result + Util.getSequence(seq);            }        } catch (Exception e) {            //根据内存生成自增ID            result = result + "MM" + String.valueOf(Math.abs(UUID.randomUUID().getMostSignificantBits())).substring(0, 8);        }                 return result;            }

 

/**     * 自增编号范围在[10000,999999999999]，不足补0     *      * @param seq     * @return     * @author jqlin     */    public static String getSequence(long seq) {        long defaultLength = 9999L;        long maxLength = 999999999999L;                if(seq >= maxLength) {            return String.valueOf(maxLength);        }                if(seq > defaultLength) {            return String.valueOf(seq);        }                  int len = 5 - String.valueOf(seq).length();        StringBuilder sb = new StringBuilder();        for (int i = 0; i < len; i++) {            sb.append('0');        }        sb.append(seq);        return sb.toString();    }