什么时候使用线程，什么时候使用线程池？

Question

任何人都可以在这个示例中指导我 Thread 和 ThreadPool 它们之间有什么区别？哪个更好用...？缺点是什么？

我使用了一个线程池，为什么在这种情况下使用它 true 或 false ？

import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.Semaphore;

class ThreeThread implements Runnable {

    String c;
    Semaphore s1;
    Semaphore s2;

    public ThreeThread(String s, Semaphore s1, Semaphore s2) {
        this.c = s;
        this.s1 = s1;
        this.s2 = s2;
    }

    @Override
    public void run() {
        while (true) {
            try {
                s1.acquire();
                Thread.sleep(400);
                System.out.println(c);
                s2.release();
            } catch (InterruptedException e) {
                // TODO Auto-generated catch block
                System.out.println(e);
            }
        }
    }

    public static void main(String[] args) {
        Semaphore sm1 = new Semaphore(1);
        Semaphore sm2 = new Semaphore(0);
        Semaphore sm3 = new Semaphore(0);

        ExecutorService es = Executors.newFixedThreadPool(3);

        es.execute(new ThreeThread("1", sm1, sm2));
        es.execute(new ThreeThread("2", sm2, sm3));
        es.execute(new ThreeThread("3", sm3, sm1));
    }
}

Answer 1

参见 ThreadPoolExecutor 的文档：

Thread pools address two different problems:

they usually provide improved performance when executing large numbers of asynchronous tasks, due to reduced per-task invocation overhead,

and they provide a means of bounding and managing the resources, including threads, consumed when executing a collection of tasks.

Each ThreadPoolExecutor also maintains some basic statistics, such as the number of completed tasks.

Answer 2

嗯，我认为 ThreadPoolExecutor 提供更好的性能，因为它管理线程池，最大限度地减少实例化新线程、分配内存的开销...

如果您要启动数千个线程，它会为您提供一些您必须自己编程的排队功能...

Threads & Executors 是不同的工具，用在不同的场景。。。在我看来，就像在问为什么可以用HashMap 还要用ArrayList？他们是不同的...

Answer 3

何时使用：线程：我想自己管理线程创建，决定创建时间，监控，同步，线程清理。

执行者：我希望specialist/manager执行这些活动。

什么时候使用线程，什么时候使用线程池？

When to use a Thread and when to use a Threadpool?

java

multithreading

threadpool