Unable to set headers in HttpsUrlConnection in AndroidApp

Question

I am creating an HttpsUrlConnection from a URL class. I am adding some header fields in the connection using the setRequestPropety method as demonstrated in following code.

URL url = new URL(address);
HttpURLsConnection connection = (HttpsURLConnection) url.openConnection();
connection.disconnect();
connection.setRequestProperty("Accept", "application/json");

I am getting exception, java.lang.IllegalStateException: Cannot set request property after connection is made upon execution of setRequestMethod. I even tried disconnection the connection as indicated in code above.

Thank you in advance.

NOTE: I also tried replacing setRequestProperty with addRequestProperty but no difference in exception.

NOTE: The stack trace is as below

10-27 13:53:40.352 29470-30420/com.MYCOM.po E/AndroidRuntime: FATAL EXCEPTION: AsyncTask #2
10-27 13:53:40.352 29470-30420/com.MYCOM.po E/AndroidRuntime: Process: com.MYCOM.po, PID: 29470
10-27 13:53:40.352 29470-30420/com.MYCOM.po E/AndroidRuntime: java.lang.RuntimeException: An error occured while executing doInBackground()
10-27 13:53:40.352 29470-30420/com.MYCOM.po E/AndroidRuntime:     at android.os.AsyncTask$3.done(AsyncTask.java:300)
10-27 13:53:40.352 29470-30420/com.MYCOM.po E/AndroidRuntime:     at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:355)
10-27 13:53:40.352 29470-30420/com.MYCOM.po E/AndroidRuntime:     at java.util.concurrent.FutureTask.setException(FutureTask.java:222)
10-27 13:53:40.352 29470-30420/com.MYCOM.po E/AndroidRuntime:     at java.util.concurrent.FutureTask.run(FutureTask.java:242)
10-27 13:53:40.352 29470-30420/com.MYCOM.po E/AndroidRuntime:     at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:231)
10-27 13:53:40.352 29470-30420/com.MYCOM.po E/AndroidRuntime:     at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
10-27 13:53:40.352 29470-30420/com.MYCOM.po E/AndroidRuntime:     at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
10-27 13:53:40.352 29470-30420/com.MYCOM.po E/AndroidRuntime:     at java.lang.Thread.run(Thread.java:818)
10-27 13:53:40.352 29470-30420/com.MYCOM.po E/AndroidRuntime:  Caused by: java.lang.IllegalStateException: Cannot set request property after connection is made
10-27 13:53:40.352 29470-30420/com.MYCOM.po E/AndroidRuntime:     at com.android.okhttp.internal.http.HttpURLConnectionImpl.setRequestProperty(HttpURLConnectionImpl.java:496)
10-27 13:53:40.352 29470-30420/com.MYCOM.po E/AndroidRuntime:     at com.android.okhttp.internal.http.DelegatingHttpsURLConnection.setRequestProperty(DelegatingHttpsURLConnection.java:258)
10-27 13:53:40.352 29470-30420/com.MYCOM.po E/AndroidRuntime:     at com.android.okhttp.internal.http.HttpsURLConnectionImpl.setRequestProperty(HttpsURLConnectionImpl.java:25)
10-27 13:53:40.352 29470-30420/com.MYCOM.po E/AndroidRuntime:     at com.MYCOM.po.LoginActivity$UserLoginTask.doInBackground(LoginActivity.java:386)
10-27 13:53:40.352 29470-30420/com.MYCOM.po E/AndroidRuntime:     at com.MYCOM.po.LoginActivity$UserLoginTask.doInBackground(LoginActivity.java:364)

NOTE: I am using the LoginActivity template, provided by Studio; to connect application to a RESTful web service.

The doInBackground method is as below

    @Override
    protected Boolean doInBackground(Void... params) {

        try {

            URL url = new URL(address);// Stored as a field in AsyncTask

            HttpURLConnection connection;
            connection = (HttpURLConnection) url.openConnection();
            connection.setRequestMethod("POST");
            connection.setRequestProperty("REST-API-Key", "HEXKEY");
            connection.setRequestProperty("Accept", "application/json");
            StringBuilder paramBuilder = new StringBuilder();
            paramBuilder.append("PARAM1=");
            paramBuilder.append("VALUE1");
            paramBuilder.append("&");
            paramBuilder.append("PARAM2=VALUE2");
            paramBuilder.append("&");
            paramBuilder.append("PARAM3=");
            paramBuilder.append("VALUE3");
            connection.setDoOutput(true);
            OutputStreamWriter outputWriter = new OutputStreamWriter(connection.getOutputStream());
            outputWriter.write(paramBuilder.toString());
            outputWriter.flush();
            if(connection == null) {
                Thread.sleep(2000);
                return false;
            }
            BufferedReader responseReader = new BufferedReader(new InputStreamReader(connection.getInputStream()));
            if(responseReader == null){
                throw new IOException("Null Response");
            }
            StringBuilder sb = new StringBuilder();
            String line;
            while((line = responseReader.readLine())!=null){
                sb.append(line+"\n");
            }
            String resp = sb.toString();
            connection.disconnect();


        } catch (InterruptedException|IOException e) {
            return false;
        }


        // TODO: register the new account here.
        return true;
    }

Answer 1

Strange, But I removed all the break points, except the last one to check the result and It worked. I guess the delays,caused by breakpoints; was the problem. I still don't get it why it is getting connected even if connection.connect() was not getting executed. The solution was not to interrupt network operations.