線程池+返回值Future

ExecutorService executor = Executors.newSingleThreadExecutor();
                // 使用Callable接口做爲構造參數
		FutureTask<String> future = new FutureTask<String>(new Callable<String>() {
			public String call() throws InterruptedException {
				// 真正的任務在這裏執行，這裏的返回值類型爲String，能夠爲任意類型
				return "call 返回數值！！";
			}
		});
		executor.execute(future);
		// 在這裏能夠作別的任何事情
		try {
			String result = future.get(2000, TimeUnit.MILLISECONDS); 
			System.out.println(result);
		} catch (InterruptedException e) {
			future.cancel(true);
		} catch (ExecutionException e) {
			future.cancel(true);
		} catch (TimeoutException e) {
			future.cancel(true);
		} finally {
			executor.shutdown();
		}