Databases
StackOverflow2013
Postsdbo
POWhy HTTP POST is not working unless we read the POST response from server?
 

Note that there are some explanatory texts on larger screens.

plurals
  1. POWhy HTTP POST is not working unless we read the POST response from server?
    primarykey
    data
    text
    <p>I am writing a uploader class for a site and in that, after uploading the files, I am reading the upload response from that site. If I didn't read the response, then the file is not getting uploaded. My code is as follows,</p> <pre><code> String charset = "UTF-8"; File binaryFile = new File("C:\\TestVideoFile.flv"); String boundary = Long.toHexString(System.currentTimeMillis()); System.out.println(boundary);// Just generate some unique random value. String CRLF = "\r\n"; // Line separator required by multipart/form-data. URLConnection connection = new URL(UPLOAD_URL).openConnection(); connection.setDoInput(true); connection.setDoOutput(true); connection.setRequestProperty("Content-Type", "multipart/form-data; boundary=" + boundary); PrintWriter writer = null; try { OutputStream output = connection.getOutputStream(); writer = new PrintWriter(new OutputStreamWriter(output, charset), true); // true = autoFlush, important! writer.append("--" + boundary).append(CRLF); writer.append("Content-Disposition: form-data; name=\"file\"; filename=\"" + binaryFile.getName() + "\"").append(CRLF); writer.append("Content-Type: " + URLConnection.guessContentTypeFromName(binaryFile.getName())).append(CRLF); writer.append("Content-Transfer-Encoding: binary").append(CRLF); writer.append(CRLF).flush(); InputStream input = null; try { input = new FileInputStream(binaryFile); long filelen = binaryFile.length(); System.out.println("Length : " + filelen); int dataRead = 0; byte[] buffer = new byte[1024]; for (int length = 0; (length = input.read(buffer)) &gt; 0;) { output.write(buffer, 0, length); } System.out.println("Now only terminating the file write loop"); output.flush(); // Important! Output cannot be closed. Close of writer will close output as well. } catch (Exception e) { System.out.println(e); } finally { if (input != null) { try { input.close(); } catch (IOException logOrIgnore) { System.out.println(logOrIgnore); } } } writer.append(CRLF).flush(); // CRLF is important! It indicates end of binary boundary. // End of multipart/form-data. writer.append("--" + boundary + "--").append(CRLF); System.out.println("Sending username"); // Send normal param. writer.append("--" + boundary).append(CRLF); writer.append("Content-Disposition: form-data; name=\"user\"").append(CRLF); writer.append("Content-Type: text/plain; charset=" + charset).append(CRLF); writer.append(CRLF); writer.append(username).append(CRLF).flush(); System.out.println("Sending password"); writer.append("--" + boundary).append(CRLF); writer.append("Content-Disposition: form-data; name=\"password\"").append(CRLF); writer.append("Content-Type: text/plain; charset=" + charset).append(CRLF); writer.append(CRLF); writer.append(password).append(CRLF).flush(); System.out.println("Reading response from server"); BufferedReader br = new BufferedReader(new InputStreamReader(connection.getInputStream())); String k = "", tmp = ""; while ((tmp = br.readLine()) != null) { System.out.println(tmp); k += tmp; } if (k.contains("Successfully")) { System.out.println("File Uploaded successfully into PutLocker :)"); String downloadLink = parseResponse(k, "&lt;link&gt;", "&lt;/link&gt;"); System.out.println("Download Link : " + downloadLink); } else { System.out.println("Upload failed :("); } } catch (Exception e) { System.out.println(e); } finally { if (writer != null) { writer.close(); } } </code></pre> <p>As you can see, I am writing the data into the server in the following line,</p> <pre><code>for (int length = 0; (length = input.read(buffer)) &gt; 0;) { output.write(buffer, 0, length); } </code></pre> <p>But after this, I have to do the following,</p> <pre><code> BufferedReader br = new BufferedReader(new InputStreamReader(connection.getInputStream())); String k = "", tmp = ""; while ((tmp = br.readLine()) != null) { System.out.println(tmp); k += tmp; } </code></pre> <p>Why do I have to read the response from server to make the upload successful? </p> <p>Can anybody explain on this?</p> <p>Thanks in advance.</p>
    singulars
    1. PO
      singulars
      1. PTAnswer
    1. This table or related slice is empty.
    1. PTQuestion
    1. This table or related slice is empty.
    1. USDinesh
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PO
      singulars
      1. PTAnswer
    1. This table or related slice is empty.
    1. COWhy can't you do `output.close()` after `output.flush()`?
      singulars
      1. POWhy HTTP POST is not working unless we read the POST response from server?
      1. USJake Stoeffler
    2. COI tired closing the output stream. That doesn't have any significance for successful file upload.
      singulars
      1. POWhy HTTP POST is not working unless we read the POST response from server?
      1. USDinesh
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload