class ThreadsEngine {

	public static void clearThreadPool() {
		for (ExecutorService pool:threadPool) {
			pool.shutdown();
		}
		
		for (ExecutorService pool:threadPool) {
			try {
				pool.awaitTermination(10, TimeUnit.SECONDS);
			} catch (InterruptedException e) {
				e.printStackTrace();
			}
		}
		
		threadPool.clear();
	}

}