class UUID {

    public String nextID() {
        // MACHINE_ID + JVM_ID + 当前时间 + counter
        return instanceId + "-" + StringUtil.longToString(System.currentTimeMillis(), noCase) + "-"
                + StringUtil.longToString(counter.getAndIncrement(), noCase);
    }

    public  UUID();
    public  UUID(boolean noCase);

}