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Requesting through HTTPURLConnection Transfer-Enconding chunked

I'm trying to get data from a API's endpoint and I have noticed the data I'm trying to get by HTTP POST method is huge and the API's server respond me with a response with one of headers set as Transfer-Encoding: chunked and I'd like to read the whole data. In my code I'm using the java.net.HttpURLConnection to establish my post request and read the data as showed bellow.
Unfortunately for this scenario I'm getting java.io.IOException: Premature EOF at the line where I read from the BufferedReader(while((output = br.readLine()) != null)) I debugged it and I'm getting status http 200 until right before the Exception has been threw.
Is there anything wrong in requesting chunked data like showed in my code?
Thank you.
String responseStr = "";
HttpURLConnection connection = null;
try {
connection = (HttpURLConnection) new URL(this.url).openConnection();
connection.setRequestProperty("content-type", "application/json");
connection.setRequestProperty("Accept", "application/json");
connection.setDoOutput(true);
OutputStream os = connection.getOutputStream();
os.write(payloadToBeRequested.getBytes());
os.flush();
BufferedReader br = new BufferedReader(new InputStreamReader(connection.getInputStream()));
String output = "";
while((output = br.readLine()) != null){
responseStr = responseStr + output;
}
status = connection.getResponseCode();
connection.disconnect();
}catch(MalformedURLException ex){
ex.printStackTrace();
}catch(IOException ex){
ex.printStackTrace();
}

Simulate URL entering on java

So I have a problem where if I type this link on the browser and hit enter, an activation happens. I just want to do the same through Java. I don't need any kind of response from the URL. It should just do the same as entering the URL on a browser. Currently my code doesn't throw an error, but I don't think its working because the activation is not happening. My code:
public static void enableMachine(String dns){
try {
String req= "http://"+dns+"/username?username=sputtasw";
URL url = new URL(req);
URLConnection connection = url.openConnection();
connection.connect();
/*BufferedReader br = new BufferedReader(new InputStreamReader(url.openStream()));
String strTemp = "";
while (null != (strTemp = br.readLine())) {
System.out.println(strTemp);
}*/
} catch (Exception ex) {
ex.printStackTrace();
}
}
What's the problem?

If you want to do that with an URLConnection, it isn't sufficient to just open the connection with connect, you also have to send e.g. an HTTP request etc.
That said, i think it would be easier, if you use an HTTP client like the one from Apache HttpComponents (http://hc.apache.org/). Just do a GET request with the HTTP client, this would be the same as visiting the page with a browser (those clients usually also supports redirection etc.).

You may use HttpUrlConnectionClass to do the job:
URL url = new URL("http://my.url.com");
HttpURLConnection httpCon = (HttpURLConnection) url.openConnection();
httpCon.setRequestProperty("Content-Type", "application/json");
httpCon.setDoOutput(true);
httpCon.setRequestMethod("POST");
String params = "foo=42&bar=buzz";
DataOutputStream wr = new DataOutputStream(httpCon.getOutputStream());
wr.writeBytes(params);
wr.flush();
wr.close();
httpCon.connect();
int responseCode = httpCon.getResponseCode();
You may as well use "GET" request method and just append parameters to the url.

How to get the Response Back from the Remote Server using an HttpURLConnection Object?

I am trying to send an HTTP POST Request to a remote server using an instance of the HttpURLConnection class. Although, I am able to get a response code and a response message, when I try to write the input stream into a StringBuffer, I am not able to actually read any lines.
When I analyzed the packets sent from WireShark, I noticed that a full response was being sent from the remote server. My only guess as to why I am not able to see it in the Java program is because the time in which I try to read from the InputStream is too late.
So, how do I read the immediate, full response from the remote server using my HttpURLConnection object? Below is the code that I am using:
HttpURLConnection conn = null;
String urlStr = "...";
URL url = null;
try
{
url = new URL(urlStr);
conn = (HttpURLConnection) url.openConnection();
conn.setRequestMethod("POST");
conn.setDoInput(true);
conn.setDoOutput(true);
...
BufferedReader rd = new BufferedReader(
new InputStreamReader(conn.getInputStream()));
StringBuilder sb = new StringBuilder();
String line;
while ((line = rd.readLine()) != null)
{
sb.append(line);
}
rd.close();
...
}...

Okay, never mind. It turns out that what I was looking for was in the HTTP Respone's header. So, I got what I needed by looking through its headers. ::Face Palm::

HttpURLConnection performs always a GET request instead of a POST request in spite of setDoOutput(true) and setRequestMethod("POST")

Since update to Ice Cream Sandwich, my POST request doesn't work anymore. Before ICS, this works fine:
try {
final URL url = new URL("http://example.com/api/user");
final HttpURLConnection connection = (HttpURLConnection) url
.openConnection();
connection.setRequestMethod("POST");
connection.setDoOutput(false);
connection.setDoInput(true);
connection.setRequestProperty("Content-Length", "0");
if (connection.getResponseCode() != HttpURLConnection.HTTP_OK) {
Log.w(RestUploader.class.getSimpleName(), ": response code: " + connection.getResponseMessage());
} else {
final BufferedReader reader = new BufferedReader(
new InputStreamReader(connection.getInputStream()));
final String line = reader.readLine();
reader.close();
return Long.parseLong(line);
}
} catch (final MalformedURLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (final ProtocolException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (final IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return -1;
I've tried to set
connection.setDoOutput(true);
but it doesn't works. The server response is always a 405 (Method not allowed) and the server log says it was an GET request.
The Android JavaDoc to setRequestMethod says:
This method can only be called before the connection is made.
Does it mean that the method must be invoked before url.openConnection()? How should I create a HttpURLConnection instance? All the examples I've seen, make it as described above.
I hope someone has an idea why it always send a GET request instead of a POST.
Thanks in advance.

connection.setRequestMethod("POST");
connection.setDoOutput(false);
In above two statements just place
connection.setDoOutput(true)
before
connection.setRequestMethod("POST")
statement

My .htaccess had a rewrite rule which redirected www to http://. Turned out my Java code worked just fine! The redirect/rewrite rule made my 1st request (POST) to forward to http and therefore "became" a GET. My PHP script was listening to POST only, and man did I scratch my head until I found my own mistake having that redirect rule. Check yours for this kind of "problem".
For me, setting either setDoOutput or setRequestMethod first does not matter, any order works (API 23). At the moment things are in this order:
HttpURLConnection con = (HttpURLConnection) obj.openConnection();
con.setInstanceFollowRedirects(false);
con.setUseCaches(false);
con.setRequestMethod("POST");
con.setDoOutput(true);
con.setRequestProperty("Content-Type",bla bla
con.setRequestProperty("Accept-Charset", "UTF-8");
con.setRequestProperty("Content-Length", String.valueOf(PARAMETER_VARIABLE.getBytes().length));
con.setFixedLengthStreamingMode(PARAMETER_VARIABLE.getBytes().length);
OutputStream os = con.getOutputStream();
os.write(PARAMETER_VARIABLE.getBytes());
os.flush();
os.close();

Java HttpURLConnection - POST with Cookie

I´m trying to send a post request with cookies. This is the code:
try {
String query = URLEncoder.encode("key", "UTF-8") + "=" + URLEncoder.encode("value", "UTF-8");
String cookies = "session_cookie=value";
URL url = new URL("https://myweb");
HttpsURLConnection conn = (HttpsURLConnection) url.openConnection();
conn.setRequestProperty("Cookie", cookies);
conn.setRequestMethod("POST");
conn.setDoInput(true);
conn.setDoOutput(true);
DataOutputStream out = new DataOutputStream(conn.getOutputStream());
out.writeBytes(query);
out.flush();
out.close();
BufferedReader in = new BufferedReader(new InputStreamReader(conn.getInputStream()));
String decodedString;
while ((decodedString = in.readLine()) != null) {
System.out.println(decodedString);
}
in.close();
// Send the request to the server
//conn.connect();
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
The problem is the request is sent without the cookies. If I only make:
conn.connect(); and don´t send data, the cookies are sent OK.
I can´t check exactly what is happening, because the connection is thorugh SSL. I only check the response.

According to the URLConnection javadoc:
The following methods are used to access the header fields and the
contents AFTER the connection is made to the remote object:
* getContent
* getHeaderField
* getInputStream
* getOutputStream
Have you confirmed that in your test case above the request is getting to the server at all? I see you have the call to connect() after getOutputStream() and commented-out besides. What happens if you uncomment it and move up before the call to getOutputStream() ?