import java.util.concurrent.*;
import java.util.Date;
import java.util.List;
import java.util.ArrayList;

public class Test implements Callable<Object>{

    private String taskNum;

    Test(String taskNum) {
        this.taskNum = taskNum;
    }

    public static void main(String[] args) throws ExecutionException,InterruptedException {
        System.out
 
.println("----程式開始執行----");
        Date date1 = new Date();
        int taskSize = 5;
        // 建立一個執行緒池
        ExecutorService pool = Executors.newFixedThreadPool(taskSize);
        // 建立多個有返回值的任務
        List<Future> list = new ArrayList<Future>();
        for (int i = 0; i < taskSize; i++) {
            Callable c = new
 
 Test(i + " ");
            // 執行任務並獲取Future物件
            Future f = pool.submit(c);
            list.add(f);
        }
        // 關閉執行緒池
        pool.shutdown();
        // 獲取所有併發任務的執行結果
        for (Future f : list) {
            // 從Future物件上獲取任務的返回值，並輸出到控制檯
            System.out.println(">>>"
 
 + f.get().toString());
        }
        Date date2 = new Date();
        System.out.println("----程式結束執行----，程式執行時間【" + (date2.getTime() - date1.getTime()) + "毫秒】");
    }

    public Object call() throws Exception {
        System.out.println(">>>" + taskNum + "任務啟動");
        Date dateTmp1 = new Date();
        Thread.sleep(1000);
        Date dateTmp2 = new Date();
        long time = dateTmp2.getTime() - dateTmp1.getTime();
        System.out.println(">>>" + taskNum + "任務終止");
        return taskNum + "任務返回執行結果,當前任務時間【" + time + "毫秒】";
    }
}