多线程下载图片

多线程下载图片

以下代码从网上下载三张图片，使用3个线程，每个线程下载一张：

package com.cxf.multithread.download;

import org.apache.commons.io.FileUtils;

import java.io.File;
import java.io.IOException;
import java.net.URL;

public class TestForDownload {
    public static void main(String[] args) {
        MyThread myThread1 = new MyThread("https://gimg2.baidu.com/image_search/src=http%3A%2F%2Finews.gtimg.com%2Fnewsapp_match%2F0%2F11355207257%2F0.jpg&refer=http%3A%2F%2Finews.gtimg.com&app=2002&size=f9999,10000&q=a80&n=0&g=0n&fmt=jpeg?sec=1636445046&t=47ce32847abf04e7b5b5f49f0d98729b","diga1.jpg");
        MyThread myThread2 = new MyThread("https://gimg2.baidu.com/image_search/src=http%3A%2F%2Fwx1.sinaimg.cn%2Fmw690%2F0076Fpdqly1guvd1sr5v6j60et08cdg002.jpg&refer=http%3A%2F%2Fwx1.sinaimg.cn&app=2002&size=f9999,10000&q=a80&n=0&g=0n&fmt=jpeg?sec=1636445491&t=f8933790c9614a327d3af045d452c778","diga2.jpg");
        MyThread myThread3 = new MyThread("https://gimg2.baidu.com/image_search/src=http%3A%2F%2Fpic.fxxz.com%2Fup%2F2021-1%2F16118024003330167.jpg&refer=http%3A%2F%2Fpic.fxxz.com&app=2002&size=f9999,10000&q=a80&n=0&g=0n&fmt=jpeg?sec=1636445613&t=7cf2449872dec9de14b101f66dcc772c","diga3.jpg");

        myThread1.start();
        myThread2.start();
        myThread3.start();
    }
}

class WebDownloader{
    public void downloader(String url,String name){
        try {
            FileUtils.copyURLToFile(new URL(url),new File(name));
        } catch (IOException e) {
            e.printStackTrace();
            System.out.println("io异常，downloader方法出现问题");
        }
    }
}

class MyThread extends Thread{
    private String url;
    private String name;
    public MyThread(String url,String name){
        this.url = url;
        this.name =name;
    }
    public void run(){
        WebDownloader webDownloader = new WebDownloader();
        webDownloader.downloader(url,name);
        System.out.println("下载了文件：" + name);
    }
}

FileUtil来自于commons-io（已经写好的jar包，可从网上下载）。

输出结果：

下载了文件：diga2.jpg
下载了文件：diga3.jpg
下载了文件：diga1.jpg

按顺序开启线程，而线程不按开启顺序结束。