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FutureTask设置方法执行的超时时间

import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.FutureTask;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;

/**
 * 设置方法执行的超时时间,超过指定的时间里没有执行完毕,则抛出异常。
 * 注意:最后得把FutureTask给cancel掉,如果FutureTask代码块里,包含有try catch代码块,
这时没有把FutureTask给cancel掉话,会一直执行直到任务执行完毕。会导致设置的任务超时不生效的情况。
 * 问题: 线程池最好不用newSingleThreadExecutor,高并发访问下有可能会导致数据不对??
 * 
 * @author cenjianteng
 */
public class FutureDemo {

	// 1、创建线程池
	private ExecutorService executorService = Executors.newFixedThreadPool(3);

	public void futureTaskDemo() {
		//2、创建一个执行任务
		FutureTask<String> future = new FutureTask<>(() -> {
			//业务逻辑
			for (int i = 0; i < 10; i++) {
				try {
					int j = 1 / 0;
				} catch (Exception e) {
					System.out.println(e);
				}
				Thread.sleep(1000);
			}
			System.out.println("***********************");
			return "success";
		});
		
		try {
			//3、执行任务
			executorService.execute(future);
			//4、任务5秒钟后没有执行完毕则抛出异常
			String result = future.get(5, TimeUnit.SECONDS);
			System.out.println("result:" + result);
		} catch (TimeoutException e) {
			System.out.println("执行任务超时了!");
//			return;
		} catch (Exception e) {
			System.out.println("fail:"+e);
		} finally {
			System.out.println("cancel");
			//6、cancel任务
			future.cancel(true);
//			executorService.shutdown();
		}
		System.out.println("FutureTask end.................");
	}

	
	//测试
	public static void main(String[] args) {
		FutureDemo demo = new FutureDemo();
		
		Runnable runnable1 = () -> {
			for (int i = 0; i < 2; i++) {
				System.out.println("Runnable1 start");
				demo.futureTaskDemo();
				System.out.println("Runnable1 end");
			}
		};
		Runnable runnable2 = () -> {
			for (int i = 0; i < 2; i++) {
				System.out.println("Runnable2 start");
				demo.futureTaskDemo();
				System.out.println("Runnable2 end");
			}
		};
		Thread thread1 = new Thread(runnable1);
		Thread thread2 = new Thread(runnable2);
		thread1.start();
		thread2.start();
		
	}

}