setRequestProperty throwing java.lang.IllegalStateException: Cannot set request property after connection is made

Question

I am getting java.lang.IllegalStateException:

java.lang.IllegalStateException: Cannot set request property after connection is made error w

Answer 1

i found the problem it's about ordering the code, if you are trying to add header and post parameters both, it's important to be careful about this

HttpURLConnection connection = (HttpURLConnection) urlConnection;

////        Add Request Headers
for (NameValuePair nvp :
         request[0].getHeaderParams()) {
     connection.setRequestProperty(nvp.getName(),nvp.getValue());
     }
// done

connection.setDoInput(true);
connection.setDoOutput(true);
connection.setRequestMethod("POST");
////         Add Post Parameters
OutputStream outputStream = urlConnection.getOutputStream();
BufferedWriter bufferedWriter = new BufferedWriter(new OutputStreamWriter(outputStream));
List params = new ArrayList<>(request[0].getPostParams());
bufferedWriter.write(getQuery(params));

// done
connection.setConnectTimeout(3000);
connection.setReadTimeout(3000);
bufferedWriter.flush();
bufferedWriter.close();
outputStream.flush();
outputStream.close();
connection.connect();

in here, i have added header parameters then set setDoInput and setDoOutput then setRequestMethod and finally you can add POST parameters. i don't know what is wrong with setRequestMethod but i think its preparing the connection by opening it or something and that's why it throws exception