【四二学堂】java从远程url文件流读取文件,并且下载到本地

2023-02-17 00:00:00 文件 读取 学堂

 java从远程url文件流读取文件,并且下载到本地(写个循环就可实现批量)

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

public class FileUtils {
    /**
     * 获取远程文件
     *
     * @param remoteFilePath 远程文件路径
     * @param localFilePath  本地文件路径
     */
    public static void downloadFile(String remoteFilePath, String localFilePath) {
        URL urlfile = null;
        HttpURLConnection httpUrl = null;
        BufferedInputStream bis = null;
        BufferedOutputStream bos = null;

        File f = new File(localFilePath);
        try {
            urlfile = new URL(remoteFilePath);
            httpUrl = (HttpURLConnection) urlfile.openConnection();
            httpUrl.connect();
            bis = new BufferedInputStream(httpUrl.getInputStream());
            bos = new BufferedOutputStream(new FileOutputStream(f));
            int len = 2048;
            byte[] b = new byte[len];
            while ((len = bis.read(b)) != -1) {
                bos.write(b, 0, len);
            }
            bos.flush();
            bis.close();
            httpUrl.disconnect();
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            try {
                bis.close();
                bos.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }


}

使用方法

//如果链接包含中文,需要转码
String resultWordPath = URLEncoderUtils.encode(wordPath);

String fileName = System.currentTimeMillis() + "";
String localPath = Constant.FILE_SAVE_PATH + "/doc/" + fileName + ".doc";

FileUtils.downloadFile(resultWordPath, localPath);

转码工具类

import java.io.UnsupportedEncodingException;
import java.net.URLEncoder;

public class URLEncoderUtils {
    public static String encode(String url) {
        try {
            String resultURL = "";
            //遍历字符串
            for (int i = 0; i < url.length(); i++) {
                char charAt = url.charAt(i);
                //只对汉字处理
                if (isChineseChar(charAt)) {
                    String encode = URLEncoder.encode(charAt + "", "UTF-8");
                    resultURL += encode;
                } else {
                    resultURL += charAt;
                }
            }
            return resultURL;
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        }
        return null;
    }

    //判断汉字的方法,只要编码在\u4e00到\u9fa5之间的都是汉字
    public static boolean isChineseChar(char c) {
        return String.valueOf(c).matches("[\u4e00-\u9fa5]");
    }

}

 

    原文作者:舟中尽敌国
    原文地址: https://blog.csdn.net/qq_38187437/article/details/108408452
    本文转自网络文章,转载此文章仅为分享知识,如有侵权,请联系博主进行删除。

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