1.認識Executor介面  最頂層介面

package com.hpd.executor;

import java.util.concurrent.Executor;

public class T01_MyExecutor implements Executor {

    public static void main(String[] args) {
        new T01_MyExecutor().execute(()->System.out.println("helllo executor"));
    }

    @Override
    
 
public void execute(Runnable command) {
        //new Thread(command).start();//開啟一個執行緒去呼叫
        command.run();//直接的方法呼叫
    }

}

2.ExecutorService介面  （繼承自Executor介面）

　　除了繼承的executor（）方法外，還提供了submit（Callable<T> task）方法,submit(Runnable task)

3Executors工具類

4ThreadPool

package com.hpd.executor;

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

import javax.swing.plaf.synth.SynthSplitPaneUI;

public class T02_ThreadPool {

    public static void main(String[] args) throws InterruptedException {
        ExecutorService service 
 
= Executors.newFixedThreadPool(5);
        for(int i=0;i<6;i++) {
            service.execute(()->{
                try {
                    TimeUnit.MICROSECONDS.sleep(500);
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
                System.out.println(Thread.currentThread().getName());
            });
        }
        System.out.println(service);
        
        service.shutdown();
        System.out.println(service.isTerminated());
        System.out.println(service.isShutdown());
        System.out.println(service);
        
        TimeUnit.MICROSECONDS.sleep(5000);
        System.out.println(service.isTerminated());
        System.out.println(service.isShutdown());
        System.out.println(service);
        
        
    }

}

[email protected][Running, pool size = 5, active threads = 5, queued tasks = 1, completed tasks = 0]
false
true
[email protected][Shutting down, pool size = 5, active threads = 5, queued tasks = 1, completed tasks = 0]
pool-1-thread-2
pool-1-thread-4
pool-1-thread-1
pool-1-thread-5
pool-1-thread-3
pool-1-thread-2
true
true
[email protected][Terminated, pool size = 0, active threads = 0, queued tasks = 0, completed tasks = 6]

5FutureTask和Future

package com.hpd.executor;

import java.util.concurrent.ExecutionException;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.Future;
import java.util.concurrent.FutureTask;
import java.util.concurrent.TimeUnit;

public class T03_Future {

    public static void main(String[] args) throws InterruptedException, ExecutionException {
        FutureTask<Integer> task = new FutureTask<>(()-> {   //用FurureTask包裝Callable任務
            TimeUnit.MILLISECONDS.sleep(500); //Thread只能傳入FutureTask不能傳入Callable
            return 1000;
        });
        new Thread(task).start();
        System.out.println(task.get());//阻塞
        
        ExecutorService service = Executors.newFixedThreadPool(5);
        Future<Integer> f= service.submit(()->{ //submit方法直接傳入Callable任務
            TimeUnit.MICROSECONDS.sleep(500);
            return 1;
        });
        System.out.println(f.isDone());
        
    }

}

6.------