Databases
StackOverflow2013
Postsdbo
POHow to upload binary file using URLConnection
 

Note that there are some explanatory texts on larger screens.

plurals
  1. POHow to upload binary file using URLConnection
    primarykey
    data
    text
    <p>In order to upload a binary file to an URL, I have been advised to use <a href="https://stackoverflow.com/a/2793153/870122">this guide</a>. However, the file is not in a directory, but is stored in a BLOB field in MySql db. The BLOB field is mapped as a <code>byte[]</code> property in JPA:</p> <pre><code>byte[] binaryFile; </code></pre> <p>I have slightly modified the code taken from the guide, in this way:</p> <pre><code>HttpURLConnection connection = (HttpURLConnection ) new URL(url).openConnection(); // set some connection properties OutputStream output = connection.getOutputStream(); PrintWriter writer = new PrintWriter(new OutputStreamWriter(output, CHARSET), true); // set some headers with writer InputStream file = new ByteArrayInputStream(myEntity.getBinaryFile()); System.out.println("Size: " + file.available()); try { byte[] buffer = new byte[4096]; int length; while ((length = file.read(buffer)) &gt; 0) { output.write(buffer, 0, length); } output.flush(); writer.append(CRLF).flush(); writer.append("--" + boundary + "--").append(CRLF).flush(); } // catch and close streams </code></pre> <p>I am not using chunked streaming. The headers used are:</p> <pre><code>username and password Content-Disposition: form-data; name=\"file\"; filename=\"myFileName\"\r\nContent-Type: application/octet-stream" Content-Transfer-Encoding: binary </code></pre> <p>All the headers are received correctly by the host. It also receives the uploaded file, but unfortunately complains that the file is not readable, and asserts that the size of the received file is 37 bytes larger than the size outputed by my code.</p> <p>My knowledge of streams, connections and byte[] is too limited for grasping the way to fix this. Any hints appreciated.</p> <hr> <p>EDIT</p> <p>As suggested by the commenter, I have tried also to write the byte[] directly, without using the ByteArrayInputStream:</p> <pre><code>output.write(myEntity.getBinaryFile()); </code></pre> <p>Unfortunately the host gives exactly the same answer as the other way.</p>
    singulars
    1. PO
      singulars
      1. PTAnswer
    1. This table or related slice is empty.
    1. PTQuestion
    1. USCommunity
    1. USperissf
    plurals
    1. PL
      singulars
      1. LTLinked
    1. PL
      singulars
      1. LTLinked
    1. This table or related slice is empty.
    1. PO
      singulars
      1. PTAnswer
    1. VO
      singulars
      1. POHow to upload binary file using URLConnection
      1. This table or related slice is empty.
      1. VTUpMod
    2. VO
      singulars
      1. POHow to upload binary file using URLConnection
      1. This table or related slice is empty.
      1. VTUpMod
    3. VO
      singulars
      1. POHow to upload binary file using URLConnection
      1. USamphibient
      1. VTFavorite
    1. COWhy are you streaming the file through a BAIS? Why not just write directly from the byte array itself?
      singulars
      1. POHow to upload binary file using URLConnection
      1. USJim Garrison
    2. CO@JimGarrison Thanks for the hint, I have updated my question
      singulars
      1. POHow to upload binary file using URLConnection
      1. USperissf
    3. COWhat happens if instead of using `file.available()` you do `byte[] temp = myEntity.getBinaryFile();` and use `temp.length`? I suspect `file.available()` is off.
      singulars
      1. POHow to upload binary file using URLConnection
      1. USJim Garrison
 

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