How to send byte array from Android device to servlet

Question

I need to send some byte array from android device to Servlet. For this I try to use next code:

Servlet:

protected void doPost(HttpServletRequest request, HttpServletResponse response) throws 
ServletException, IOException {

  DataInputStream in = new DataInputStream((InputStream)request.getInputStream());
   response.setContentType("text/plain");
    byte[] buffer = new byte[1024];
    int len = 0;
    File file;
    file=new File(getServletContext().getRealPath("/POST_LOG!!!!.txt"));
    if(!file.exists()){
        file.createNewFile();
    }
    while ((len = in.read(buffer)) > 0) {
          FileOutputStream fos = new FileOutputStream(getServletContext().getRealPath("/POST_LOG!!!!.txt"), true);

           fos.write(buffer);            
           fos.close(); 
    }

    PrintWriter out = response.getWriter();
    out.write("Done");
    out.close();

Device side :

URL uploadUrl;
    try {
        uploadUrl = new URL(url);
        HttpURLConnection c = (HttpURLConnection) uploadUrl
                .openConnection();
        c.setRequestMethod("POST");

        c.setDoInput(true);
        c.setDoOutput(true);
        c.setUseCaches(false);
        c.connect();
        OutputStream out = c.getOutputStream();

        for (int i = 0; i < 1000; i++) { // generate random bytes for
                                            // uploading
            byte[] buffer = new byte[256];
            for (int j = 0; j < 256; j++) {
                Random r = new Random();
                buffer[j] = (byte) r.nextInt();
            }

            out.write(buffer);
            out.flush();
        }

        out.close();

    } catch (Exception e) {
        MessageBox("Error. " + e.toString());
    }

    return (long) 0;
}

I dont understand why this code doesnt work. When I try to debug my POST method it even not called. I will grateful for your examples

Please share your web.xml entry of servlet configuration, URL mapping and servletn URL you are using to invoke it. — Santosh
– Santosh, Commented Mar 26, 2012 at 6:45

Speise · Accepted Answer · 2012-03-27 12:00:23Z

2

I found the solution. I just changed my device-side code using custom InputStream.

Device side :

HttpPost httpPost = new HttpPost(url);
    httpPost.setEntity(new InputStreamEntity(new MyInputStream(),
            4096 * 1024 * 10));
    HttpResponse response = null;

    try {
        response = httpClient.execute(httpPost);
    } catch (ClientProtocolException e) {
        e.printStackTrace();
        httpPost.abort();
    } catch (IOException e) {
        e.printStackTrace();
        httpPost.abort();
    }

answered Mar 27, 2012 at 12:00

Speise

8191 gold badge13 silver badges31 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

Bozho · Accepted Answer · 2012-03-26 21:39:37Z

0

You have a lot of options:

send the byte values: 125,11,25,40 (that's a dumb option)
send it base64- or hex- encoded, and then decode it (use apache commons-codec)
submit it as multipart/form-data

edited Mar 26, 2012 at 21:39

answered Mar 26, 2012 at 13:56

Bozho

599k147 gold badges1.1k silver badges1.2k bronze badges

Collectives™ on Stack Overflow

How to send byte array from Android device to servlet

2 Answers 2

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related