Question

我是线程新手，所以如果请给我一个关于我案例的建议。

我想创建一个新线程来做某事我不关心这个线程是否可以完成。

我打算使用ExecutorCompletionService来完成我的工作，但这个课程不适合我。它必须调用take或poll来排空队列以避免内存泄漏。所以，这意味着我必须等到线程完成。我从这个question

中读到了这个

这是当前的代码

ExecutorService executor = Executors.newCachedThreadPool();

CompletionService<Entity> completion = new ExecutorCompletionService<>(executor);

DoSomeThingClass doSomething = getInstance();

completion.submit(doSomething);

executor.shutdown();

// Continue to do other job and I don't care whenever doSomeThing is complete.
// However when doSomeThing finish, I don't need to do anything to avoid memory leak

出于这个原因，请举例说明我的案例和一些框架代码。

非常感谢

Answer 1

您可以将此主题标记为“守护程序”。当您的主线程完成后，您的应用就会退出。

    public static void main(String[] args)
    {
    Thread t = new Thread(new Runnable() {
        @Override
        public void run() {
            try {
                TimeUnit.SECONDS.sleep(2);
            } catch(InterruptedException e) {}
            System.out.println("Thread 2 is finished");

        }
    });
    t.setDaemon(true);
    t.start();
    System.out.println("Thread 1 is finished");
}

Answer 2

您可以使用Spring TaskExecutor，提升线程来运行任务非常有用。

import org.springframework.core.task.TaskExecutor;

public class TaskExecutorExample {

    private class MessagePrinterTask implements Runnable {
        private String message;

        public MessagePrinterTask(String message) {
            this.message = message;
        }

        public void run() {
            System.out.println(message);
        }

    }

    private TaskExecutor taskExecutor;

    public TaskExecutorExample(TaskExecutor taskExecutor) {
        this.taskExecutor = taskExecutor;
    }

    public void printMessages() {
        for(int i = 0; i < 25; i++) {
            taskExecutor.execute(new MessagePrinterTask("Message" + i));
        }
    }
}

您可以在此处查看Spring Task Execution文档：

http://docs.spring.io/spring/docs/3.0.x/spring-framework-reference/html/scheduling.html

Answer 3

与您一起编写未来概念

Future ft=completion.submit(doSomething);
ft.get(timeOut, TimeUnit.MILLISECONDS);

在这里你可以指定执行线程的时间，如果它无法获得执行线程get kill（不是100％肯定）意味着它试图中断线程并试图杀死

Answer 4

我可以通过以下代码解决我的问题

public static void main(
    String[] args) {
    ExecutorService executor = Executors.newCachedThreadPool();
    executor.execute(new Runnable() {
        @Override
        public void run() {
            try {
                TimeUnit.SECONDS.sleep(2);
            } catch (InterruptedException e) {

            } finally {
                System.out.println("Thread 2 is finished");
            }
        }
    });
    executor.shutdown();
    System.out.println("Thread 1 is finished");
}

运行一个新线程，不要等待此线程完成

4 个答案: