Java多线程--使用future进行异步编程

 * 使用future进行异步编程
 * 缺点：
 * 不知道何时结束
 * 阻塞获取结果

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

public class T01_Future {

    public static void main(String[] args) throws Exception {
        ExecutorService service = Executors.newCachedThreadPool();
        Future<Integer> future = service.submit(()->{
            return 8;
        });

        int i = future.get();

        System.out.println(i);
    }

}