相關工具類代碼

import java.io.*;
import java.net.URL;
import java.net.URLConnection;

/**
 * @description: 根據文件鏈接地址下載文件
 * @author: zyb
 * @date: 2020/10/13 15:47
 */
public class DownloadFile {
    public static void main(String[] args) {
        downloadA("文件鏈接地址", "下載存放地址 + 文件名+后綴");
        downloadB("文件鏈接地址", "文件名+后綴", "下載存放地址");
    }

    /**
     * 根據鏈接地址下載文件
     * @param downloadUrl 文件鏈接地址
     * @param path        下載存放文件地址 + 文件名
     */
    private static void downloadA(String downloadUrl,String path) {
        URL url = null;
        DataInputStream dataInputStream = null;
        FileOutputStream fileOutputStream = null;
        try {
            url = new URL(downloadUrl);
            dataInputStream = new DataInputStream(url.openStream());
            fileOutputStream = new FileOutputStream(new File(path));
            ByteArrayOutputStream output = new ByteArrayOutputStream();

            byte[] buffer = new byte[1024];
            int length;

            while ((length = dataInputStream.read(buffer)) > 0) {
                output.write(buffer, 0, length);
            }
            fileOutputStream.write(output.toByteArray());
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            if (dataInputStream != null){
                try {
                    dataInputStream.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            if (fileOutputStream != null){
                try {
                    fileOutputStream.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
    }
    /**
     * @param downloadUrl 文件鏈接地址
     * @param filename    保存文件名
     * @param filePath    保存文件路徑
     */
    private static void downloadB(String downloadUrl, String filename, String filePath) {
        URL url = null;
        InputStream inputStream = null;
        OutputStream outputStream = null;
        try {
            url = new URL(downloadUrl);
            // 打開連接
            URLConnection con = url.openConnection();
            // 請求超時:5s
            con.setConnectTimeout(5 * 1000);
            inputStream = con.getInputStream();

            byte[] bytes = new byte[1024];
            // 讀取到的數據長度
            int length;
            File savePath = new File(filePath);
            if (!savePath.exists()) {
                // 如果不存在當前文件夾蝙砌，則創(chuàng)建該文件夾
                boolean mkdir = savePath.mkdirs();
                if (!mkdir) {
                    System.out.println("創(chuàng)建文件夾失敗");
                    return;
                }
            }
            outputStream = new FileOutputStream(savePath.getPath() + "\\" + filename);
            // 讀取
            while ((length = inputStream.read(bytes)) != -1) {
                outputStream.write(bytes, 0, length);
            }
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            if (inputStream != null) {
                try {
                    inputStream.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            if (outputStream != null) {
                try {
                    outputStream.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
    }
}