Java 如何将网络资源url转化为File文件

将网络资源url转化为File文件

将互联网上的http开头的url资源，保存到本地。

 private File getNetUrlHttp(String path){
       //对本地文件命名，path是http的完整路径，主要得到资源的名字
        String newUrl = path;
        newUrl = newUrl.split("[?]")[0];
        String[] bb = newUrl.split("/");
        //得到最后一个分隔符后的名字
        String fileName = bb[bb.length - 1];
        //保存到本地的路径
        String filePath="e:\\audio\\"+fileName;
        File file = null;

        URL urlfile;
        InputStream inputStream = null;
        OutputStream outputStream = null;
        try{
            //判断文件的父级目录是否存在，不存在则创建
            file = new File(filePath);
            if(!file.getParentFile().exists()){
                file.getParentFile().mkdirs();
            }
            try{
                //创建文件
                file.createNewFile();
            }catch (Exception e){
                e.printStackTrace();
            }
            //下载
            urlfile = new URL(newUrl);
            inputStream = urlfile.openStream();
            outputStream = new FileOutputStream(file);

            int bytesRead = 0;
            byte[] buffer = new byte[8192];
            while ((bytesRead=inputStream.read(buffer,0,8192))!=-1) {
                outputStream.write(buffer, 0, bytesRead);
            }
            }catch (Exception e) {
                e.printStackTrace();
            }finally {
                try {
                    if (null != outputStream) {
                        outputStream.close();
                    }
                    if (null != inputStream) {
                        inputStream.close();
                    }

                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
          return file;
        }

url转变为 MultipartFile对象

/**
 * url转变为 MultipartFile对象
 * @param url
 * @param fileName
 * @return
 * @throws Exception
 */
private static MultipartFile createFileItem(String url, String fileName) throws Exception{
    FileItem item = null;
    try {
        HttpURLConnection conn = (HttpURLConnection) new URL(url).openConnection();
        conn.setReadTimeout(30000);
        conn.setConnectTimeout(30000);
        //设置应用程序要从网络连接读取数据
        conn.setDoInput(true);
        conn.setRequestMethod("GET");
        if (conn.getResponseCode() == HttpURLConnection.HTTP_OK) {
            InputStream is = conn.getInputStream();
            FileItemFactory factory = new DiskFileItemFactory(16, null);
            String textFieldName = "uploadfile";
            item = factory.createItem(textFieldName, ContentType.APPLICATION_OCTET_STREAM.toString(), false, fileName);
            OutputStream os = item.getOutputStream();
            int bytesRead = 0;
            byte[] buffer = new byte[8192];
            while ((bytesRead = is.read(buffer, 0, 8192)) != -1) {
                os.write(buffer, 0, bytesRead);
            }
            os.close();
            is.close();
        }
    } catch (IOException e) {
        throw new RuntimeException("文件下载失败", e);
    }
    return new CommonsMultipartFile(item);
}

以上为个人经验，希望能给大家一个参考，也希望大家多多支持我们。