实现Callable接口

案例：

package com.mokuiran.thread;
​
import org.apache.commons.io.FileUtils;
​
import java.io.File;
import java.io.IOException;
import java.net.URL;
import java.util.concurrent.*;
​
//线程创建方式三：实现callable接口
​
public class CallableDemo implements Callable<Boolean> {
    private String url;//网络图片的地址
    private String name;//保存的文件名
​
    public CallableDemo(String url, String name){
        this.url = url;
        this.name = name;
    }
​
    @Override
    public Boolean call() {
        WebDownLoader2 webDownLoader2 = new WebDownLoader2();
        webDownLoader2.downloader(url,name);
        System.out.println("下载的文件名："+name);
        return true;
    }
​
    public static void main(String[] args) throws ExecutionException, InterruptedException {
        CallableDemo demo1 = new CallableDemo("/i/l/?n=22&i=blog/2941481/202207/2941481-20220730105748137-1136505936.png","代码.png");
        CallableDemo demo2 = new CallableDemo("/i/l/?n=22&i=blog/2941481/202207/2941481-20220730105748137-1136505936.png","代码2.png");
​
        //创建执行服务：
        ExecutorService ser = Executors.newFixedThreadPool(2);
​
        //提交执行
        Future<Boolean> r1 = ser.submit(demo1);
        Future<Boolean> r2 = ser.submit(demo2);
​
        //获取结果
        boolean rs1 = r1.get();
        boolean rs2 = r2.get();
​
        //关闭服务
        ser.shutdownNow();
​
    }
}
class WebDownLoader2{
    //下载方法
    public void downloader(String url,String name){
        try {
            FileUtils.copyURLToFile(new URL(url),new File(name));
        } catch (IOException e) {
            e.printStackTrace();
            System.out.println("异常，downloader()方法出现问题");
        }
    }
}