Uploading file with Java

Question

I'm trying to upload a file using Java (HTTP Post):

HttpURLConnection conn = (HttpURLConnection) new URL(_uploadTarget).openConnection();
conn.setRequestMethod("POST");
conn.setRequestProperty("Content-Type", "multipart/form-data; boundary=" + boundary);
conn.setDoOutput(true);
long fileLength = fileContentLength + tail.length();
String stringData = "--" + boundary + "\r\nContent-Disposition: form-data; name=\"metadata\"\r\n\r\n" + metadata + "\r\n" + "--" + boundary + "\r\nContent-Disposition: form-data; name=\"uploadfile\"; filename=\"" + fileName + "\"\r\nContent-Type: application/octet-stream; charset=UTF-8\r\nContent-Transfer-Encoding: binary\r\n" + "Content-length: " + fileLength + "\r\n\r\n";

long requestLength = stringData.length() + fileLength;
conn.setRequestProperty("Content-length", "" + requestLength);
conn.setFixedLengthStreamingMode((int) requestLength);
conn.connect();
DataOutputStream out = new DataOutputStream(conn.getOutputStream());

out.writeBytes(stringData);
out.flush();

int progress = 0;
int bytesRead = 0;
byte b[] = new byte[1024];
BufferedInputStream bufin = new BufferedInputStream(
        new FileInputStream(_file));
while ((bytesRead = bufin.read(b)) != -1) {
    out.write(b, 0, bytesRead);
    out.flush();
    progress += bytesRead;
}

out.writeBytes(tail);
out.flush();
out.close();

BufferedReader rd = new BufferedReader(new InputStreamReader(conn.getInputStream()));
String line;
StringBuilder sb = new StringBuilder();

while ((line = rd.readLine()) != null) {
    sb.append(line);
}

c# server:

public void ProcessRequest(HttpContext context) {
var uploadedFile = context.Request.Files[0]; // often throws exception with message: "Thread was being aborted."
}

This code works - some times. Hope someone can help.

@Riduidel Code says "// often throws exception with message: "Thread was being aborted."" in the server side script. — Kurru, Jan 06 '11 at 14:25

score 3 · Accepted Answer · edited May 23 '17 at 12:26

3

Seeing that I don't know what errors/exception you're getting, since you're uploading file(s) using HttpURLConnection, then I would suggest reading:

BalusC - How to use java.net.URLConnection to fire and handle HTTP requests?. Just scroll down to uploading files.

edited May 23 '17 at 12:26

Community

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answered Jan 06 '11 at 14:33

Buhake Sindi

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score 0 · Answer 2 · answered Jan 06 '11 at 14:50

0

Although some crucial information is missing in your code example, I think your Java part is fine since it "works sometimes" and the exception is specific to C#.

I don't do C#, but Google reveals among others your Stackoverflow question the following link: http://www.debugging.com/bug/14721. Here's an extract of relevance:

Solved it by setting the Request execution timeout timer to a little higher value than 2minutes :)

If it's true that request processing takes that long, your solution may be to set that timeout higher.

answered Jan 06 '11 at 14:50

BalusC

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You only need to configure timeout and request length in the web.config file, if you are uploading large files. I'm trying with files around 2 to 50 kb. However the other suggestion solved the issue. There's something wrong with the Java code I posted above. :-) – Martin Jan 07 '11 at 10:14

Uploading file with Java

2 Answers2