int getFreeThreadId() {
		for (int i = 0; i < this.clientHandlerThread.length; i++) {
			if (this.clientHandlerThread[i] != null && this.clientHandlerThread[i].isAlive())
				continue;
			else {
				this.log.info("get Free Thread Id: " + i);
				return i;
			}
		}
		this.log.info("get Free Thread Id: -1");
		return -1;
	}