Java，从网络URL中下载文件并保存到本地

创建Maven项目，导入Hutool工具包

    cn.hutool
    hutool-all
    5.4.5

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;



public class FileDownload {

    
    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));
    }
}