并发编程与高并发解决方案学习(J.U.C之Future、FutureTask、ForkJoin)

Callable与Runnable接口对比

Future接口

import lombok.extern.slf4j.Slf4j;

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

@Slf4j
public class FutureExample {

    static class MyCallable implements Callable<String> {

        @Override
        public String call() throws Exception {
            log.info("do something in callable");
            Thread.sleep(5000);
            return "Done";
        }
    }

    public static void main(String[] args) throws Exception {
        ExecutorService executorService = Executors.newCachedThreadPool();
        Future<String> future = executorService.submit(new MyCallable());
        log.info("do something in main");
        //Thread.sleep(10000);
        log.info("这里不阻塞，可以继续异步执行");
        String result = future.get(); //get方法会发生阻塞，如果判断任务是否执行完成使用isDone()方法
        log.info("result：{}", result);
    }
}import lombo