思路：

在程序的设计过程中涉及到了数据的返回，所以选择callable接口来实现较为方便。

代码实现：

package Demo_2_3_多线程的竞猜抢答;

import java.util.concurrent.Callable;

public class MyThread implements Callable<String> { // 泛型设置返回值类型
    private boolean flag = false;   // 抢答处理

    @Override
    public String call() throws Exception {
        synchronized (this){    // 数据同步
            if (this.flag == false){    // 抢答成功
                this.flag = true;
                return Thread.currentThread().getName() + "抢答成功！";
            }else {
                return Thread.currentThread().getName() + "抢答失败！";
            }
        }
    }
}

package Demo_2_3_多线程的竞猜抢答;

import java.util.concurrent.ExecutionException;
import java.util.concurrent.FutureTask;

public class Main {
    public static void main(String[] args) throws Exception{
        MyThread mt = new MyThread();
        FutureTask<String> task1 = new FutureTask<>(mt);
        FutureTask<String> task2 = new FutureTask<>(mt);
        FutureTask<String> task3 = new FutureTask<>(mt);
        new Thread(task1,"竞赛者A").start();
        new Thread(task2,"竞赛者B").start();
        new Thread(task3,"竞赛者C").start();
        System.out.println(task1.get());
        System.out.println(task2.get());
        System.out.println(task3.get());
        }
    }