package com.wuming.demo02;import com.sun.org.apache.xpath.internal.operations.Bool;
import org.apache.commons.io.FileUtils;import java.io.File;
import java.io.IOException;
import java.net.URL;
import java.util.concurrent.*;//练习Thread，实现多线程同步下载图片
//线程创建方式三：实现callable接口
public class TestCallable implements Callable<Boolean> {private String url;//网络图片地址private String name;//保存的文件名public TestCallable(String url,String name){this.url=url;this.name=name;}//下载图片线程的执行体@Overridepublic Boolean call() {webDown_two webDown = new webDown_two();webDown.downloader(url,name);System.out.println("下载的文件名为："+name);return true;}public static void main(String[] args) throws ExecutionException, InterruptedException {//ctrl+d快速复制三行TestCallable t1 = new TestCallable("https://lmg.jj20.com/up/allimg/tp09/210611094Q512b-0-lp.jpg","1.jpg");TestCallable t2 = new TestCallable("https://lmg.jj20.com/up/allimg/tp09/210611094Q512b-0-lp.jpg","2.jpg");TestCallable t3 = new TestCallable("https://lmg.jj20.com/up/allimg/tp09/210611094Q512b-0-lp.jpg","3.jpg");//多线程同时下载多张图片，每次执行结果不一样，占cpu多就先执行//创建执行任务：ExecutorService ser = Executors.newFixedThreadPool(3);//提交执行Future<Boolean> r1 = ser.submit(t1);Future<Boolean> r2 = ser.submit(t2);Future<Boolean> r3 = ser.submit(t3);//获取结果boolean rs1 = r1.get();boolean rs2 = r2.get();boolean rs3 = r3.get();System.out.println(rs1);System.out.println(rs2);System.out.println(rs3);//关闭ser.shutdownNow();}
}//下载器
class webDown_two{//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("IO异常，downloader方法出现问题");}}
}

下载的文件名为：3.jpg
下载的文件名为：1.jpg
下载的文件名为：2.jpg
true
true
true