Java，从网络URL中下载文件并保存到本地

Java，从网络URL中下载文件并保存到本地

1. 代码演示

1. 创建Maven项目，导入Hutool工具包

   <dependency>
       <groupId>cn.hutoolgroupId>
       <artifactId>hutool-allartifactId>
       <version>5.4.5version>
   dependency>
   

2. 代码

   import cn.hutool.core.date.BetweenFormater;
   import cn.hutool.core.date.DateTime;
   import cn.hutool.core.date.DateUnit;
   import cn.hutool.core.date.DateUtil;
   import cn.hutool.core.io.FileUtil;
   import cn.hutool.core.io.StreamProgress;
   import cn.hutool.core.io.unit.DataSizeUtil;
   import cn.hutool.core.lang.Console;
   import cn.hutool.http.HttpUtil;
   
   import java.io.File;
   import java.io.IOException;
   import java.util.UUID;
   
   
   /**
    * @className: FileDownload
    * @description: TODO
    * @author:
    * @date: 2021/11/1 19:04
    * @version: 1.0
    */
   public class FileDownload {
   
       /**
        * @return java.lang.String
        * @author
        * @description 从网络URL中下载文件
        * @date 15:33 2021/11/2
        * @params [fileUrl, diskPath]
        */
       public static Long downLoadFromUrl(String fileUrl, String diskPath) {
           String path;
           long size = 0;
           if (fileUrl != null) {
               //文件后缀
               String fileName = fileUrl.substring(fileUrl.lastIndexOf("."));
               try {
                   String uuidName = UUID.randomUUID().toString();
                   File file = new File(diskPath);
                   if (!file.exists()) {
                       //创建文件夹
                       boolean mkdir = file.mkdir();
                       if (!mkdir) {
                           throw new RuntimeException("创建文件夹失败，路径为：" + diskPath);
                       }
                   }
                   path = diskPath + File.separator + uuidName + fileName;
                   String begin = DateUtil.now();
                   DateTime beginTime = DateUtil.parse(begin);
                   //带进度显示的文件下载
                   size = HttpUtil.downloadFile(fileUrl, FileUtil.file(path), new StreamProgress() {
                       @Override
                       public void start() {
                           Console.log("开始下载，时间为：" + begin);
                       }
   
                       @Override
                       public void progress(long progressSize) {
                           Console.log("已下载：{}", FileUtil.readableFileSize(progressSize));
                       }
   
                       @Override
                       public void finish() {
                           String end = DateUtil.now();
                           DateTime endTime = DateUtil.parse(end);
                           long between = DateUtil.between(beginTime, endTime, DateUnit.MS);
                           Console.log("下载完成，用时：" + DateUtil.formatBetween(between, BetweenFormater.Level.SECOND));
                       }
                   });
               } catch (Exception e) {
                   Console.log("下载异常，异常信息为：" + e.getMessage());
               }
           }
           return size;
       }
   
       public static void main(String[] args) {
           //文件下载的URL
           String url = "......";
           //文件的存储位置
           String path = "F:\\test";
           long size = FileDownload.downLoadFromUrl(url, path);
           System.out.println("文件大小为：" + DataSizeUtil.format(size));
       }
   }
   

2. 参考资料

• Hutool