Downloaded files with whitespaces in path are damaged

Question

I have following problem. I have to download pdf files from a server and some of them have whitespaces in their names. So every file will be downloaded, but those, which have whitespaces can not be opened.

If I access this files on the server via chrome, they open well (also with the whitespace in the url).

And what I am wondering about is, that java says the files will be downloaded. But when I try to open them in Acrobat Reader, it shows me an error message, that the files are damaged. Here is the sample of my code:

public static void downloadFile(String fileURL, String saveDir) throws IOException {
    Authenticator.setDefault(new Authenticator() {
        @Override
        protected PasswordAuthentication getPasswordAuthentication() {          
            return new PasswordAuthentication("*****", "*********".toCharArray());
        }
    });

    final int BUFFER_SIZE = 4096;
    URL url = new URL(fileURL);
    HttpURLConnection httpConn = (HttpURLConnection) url.openConnection();
    String credentials = "ptt" + ":" + "ptt123";
    String encoding = Base64.getEncoder().encodeToString(credentials.getBytes(StandardCharsets.UTF_8));
    httpConn.setRequestProperty("Authorization", String.format("Basic %s", encoding));
    int responseCode = 0;
    responseCode = httpConn.getResponseCode();
    // always check HTTP response code first
    if (responseCode == HttpURLConnection.HTTP_OK) {
        String fileName = "";
        String disposition = httpConn.getHeaderField("Content-Disposition");
        String contentType = httpConn.getContentType();
        int contentLength = httpConn.getContentLength();

        if (disposition != null) {
            // extracts file name from header field
            int index = disposition.indexOf("filename=");
            if (index > 0) {
                fileName = disposition.substring(index + 10,
                        disposition.length() - 1);
            }
        } else {
            // extracts file name from URL
            fileName = fileURL.substring(fileURL.lastIndexOf("/") + 1,
            fileURL.length());
        }



        // opens input stream from the HTTP connection
        InputStream inputStream = httpConn.getInputStream();
        String saveFilePath = saveDir + File.separator + fileName;

        // opens an output stream to save into file
        FileOutputStream outputStream = new FileOutputStream(saveFilePath);

        int bytesRead = -1;
        byte[] buffer = new byte[BUFFER_SIZE];
        while ((bytesRead = inputStream.read(buffer)) != -1) {
            outputStream.write(buffer, 0, bytesRead);
        }

        outputStream.close();
        inputStream.close();

        System.out.println("File downloaded");
    } else {
        System.out.println("No file to download. Server replied HTTP code: " + responseCode);
    }
    httpConn.disconnect();
}

I also tried to replace the whitespace through "%20" in the fileUrl. So what can be the problem? As I wrote above, the files without any whitespace can be opened after the the download without any problems.

I use Java 1.7.

Cheers,

Andrej

Answer 1

if fileName contains space then replace it to some other charecter. it may work, if not please let me know.

if(fileName.trim().contains(" "))
    fileName.replace(" ","_");

Answer 2

URL url = new URL(URLEncoder.encode(fileUrl, "UTF-8"));