System.out.println("bat dau chay" + Calendar.getInstance());
Callable callable1 = new Callable() {
	@Override
	public String call() throws Exception {
		System.out.println("task 1");
		return "task --1";
	}
};
Callable callable2 = new Callable() {
	@Override
	public String call() throws Exception {
		System.out.println("task 2");
		return "task --2";
	}
};
Callable callable3 = new Callable() {
	@Override
	public String call() throws Exception {
		System.out.println("task 3");
		return "task --3";
	}
};
List<Callable> callables = new ArrayList();
callables.add(callable1);
callables.add(callable2);
callables.add(callable3);
callables.add(callable1);
callables.add(callable2);
callables.add(callable3);
callables.add(callable1);
callables.add(callable2);
callables.add(callable3);

ExecutorService executorService = Executors.newFixedThreadPool(5);
List<Future> futures = executorService.invokeAll(callables);
for (Future f : futures) {
	System.out.println(f.get());
}
System.out.println("ket thuc" + Calendar.getInstance());
executorService.shutdown();