Callable使用案例

1、两种实现方式

import java.util.concurrent.*;

public class TestSubmit {

    public Future welcome1(String name, ExecutorService executor) {
        System.out.println("方法调用线程名：" + Thread.currentThread().getName());
        return executor.submit(() -> {
            System.out.println("异步执行线程名：" + Thread.currentThread().getName()+"，执行业务中...");
            Thread.sleep(3000);
            return "hello " + name;
        });

       
    }

    public String welcome2(String name) throws ExecutionException, InterruptedException {
        System.out.println("方法调用线程名：" + Thread.currentThread().getName());
        FutureTask futureTask = new FutureTask<>(() -> {
            System.out.println("异步执行线程名：" + Thread.currentThread().getName()+"，执行业务中...");
            Thread.sleep(3000);
            return "hello " + name;
        });
        Thread t1 = new Thread(futureTask); //声明线程
        t1.start();
        return futureTask.get();
    }
    public static void main(String[] args) throws ExecutionException, InterruptedException {
        System.out.println("程序主线程名称：" + Thread.currentThread().getName()+"任务开始...");
        ExecutorService executor = Executors.newFixedThreadPool(10);
        TestSubmit testSubmit = new TestSubmit();
        Future result = testSubmit.welcome1("张明", executor);

        System.out.println("程序主线程名称：" + Thread.currentThread().getName() + ",等待异步调用执行完中...");

        System.out.println("程序主线程名称：" + Thread.currentThread().getName() +" 打印结果"+result.get());

        executor.shutdown();
        System.out.println();
        System.out.println("---------------------------");
        System.out.println();

        String res =testSubmit.welcome2("王五");
        System.out.println("程序主线程名称：" + Thread.currentThread().getName() + ",等待异步调用执行完中...");
        System.out.println("程序主线程名称：" + Thread.currentThread().getName() +" 打印结果"+res);
    }

}

2、输出结果

程序主线程名称：main任务开始...
方法调用线程名：main
程序主线程名称：main,等待异步调用执行完中...
异步执行线程名：pool-1-thread-1，执行业务中...
程序主线程名称：main 打印结果hello 张明

---------------------------

方法调用线程名：main
异步执行线程名：Thread-0，执行业务中...
程序主线程名称：main,等待异步调用执行完中...
程序主线程名称：main 打印结果hello 王五