The HTTP protocol is based on a request-response pattern: you send your request first and the server responds. Once the server responded, you can't send any more content, it wouldn't make sense.
Look at your code, you are getting the response in for loop. when one response is accessed then next time loop throw exception. If you want to create multiple request then should create new urlconnection each time. For example.

private void requestMethod(){ //your for loop goes here } private void backgroundOperation(/**required parameter*/){ // your httpurlconnection code goes here don't use for loop. use finally block to close connection also }

The HTTP protocol is based on a request-response pattern: you send your request first and the server responds. Once the server responded, you can't send any more content, it wouldn't make sense. (How could the server give you a response code **before** it knows what is it you're trying to send?)
So when you call `server.getResponseCode()`, you effectively tell the server that your request has finished and it can process it. If you want to send more data, you have to start a new request.
Looking at your code you want to check whether the connection itself was successful, but there's no need for that: if the connection isn't successful, an `Exception` is thrown by `server.connect()`. But the outcome of a connection attempt isn't the same as the HTTP response code, which always comes after the server processed all your input.