多執行緒下載圖片：

package com.cheng.thread;
​
import org.apache.commons.io.FileUtils;
​
import java.io.File;
import java.io.IOException;
import java.net.URL;
​
public class Demo02 extends Thread {
​
  private String url;//網路圖片地址
  private String name;//儲存的檔名
​
  //構造器
  public Demo02(String url,String name){//給url和name傳引數
    this.url = url;
    this.name = name;
   }
​
  @Override
  public void run() {//重寫run方法
    WebDownloader webDownloader = new WebDownloader();
    webDownloader.downloader(url,name);
    System.out.println("下載的檔名為"+name);
   }
​
  public static void main(String[] args) {
    Demo02 d2 = new Demo02("https://pics6.baidu.com/feed/a8014c086e061d95cd2f093cb0ce89d762d9ca0e.jpeg?token=f06261ea169217618d665fd6e52df6f1","鬼刀");
    d2.start();
   }
​
​
}
​
//下載器
class WebDownloader{
  //下載方法
  public void downloader(String url,String name){
    try {//捕獲異常
      FileUtils.copyURLToFile(new URL(url),new File(name));//下載儲存
     } catch (IOException e) {
      e.printStackTrace();
      System.out.println("downloader出錯了");//報錯
     }
   }
}
​