并发包---Future模式

import java.util.concurrent.Callable;
import java.util.concurrent.FutureTask;

public class FutureTest {
    public static void main(String s[]){
        FutureTask<Integer> future1 = new FutureTask<Integer>(new Test1());
        FutureTask<String> future2 = new FutureTask<String>(new Test2());
        FutureTask<Long> future3 = new FutureTask<Long>(new Test3());
        new Thread(future1).start();
        new Thread(future2).start();
        new Thread(future3).start();
        try {
            if (future1.isDone()){
                System.out.println("future1 is Done");
            }
            if (future2.isDone()){
                System.out.println("future2 is Done");
            }
            if (future3.isDone()){
                System.out.println("future3 is Done");
            }
            int i = future1.get();
            String str = future2.get();
            long l = future3.get();
            System.out.println(i+str+l);
        }catch (Exception e){
            e.printStackTrace();
        }

    }
}

class Test1 implements Callable<Integer>{
    @Override
    public Integer call() {
        try {
            Thread.sleep(1000);
        }catch (Exception e){
        }
        return 1;
    }
}

class Test2 implements Callable<String>{
    @Override
    public String call() {
        try {
            Thread.sleep(5000);
        }catch (Exception e){
        }
        return "2";
    }
}

class Test3 implements Callable<Long>{
    @Override
    public Long call() {
        try {
            Thread.sleep(10000);
        }catch (Exception e){
        }
        return 3L;
    }
}