How to add parameters to HttpURLConnection using POST using NameValuePair

You can get output stream for the connection and write the parameter query string to it.

URL url = new URL("http://yoururl.com");HttpsURLConnection conn = (HttpsURLConnection) url.openConnection();conn.setReadTimeout(10000);conn.setConnectTimeout(15000);conn.setRequestMethod("POST");conn.setDoInput(true);conn.setDoOutput(true);List<NameValuePair> params = new ArrayList<NameValuePair>();params.add(new BasicNameValuePair("firstParam", paramValue1));params.add(new BasicNameValuePair("secondParam", paramValue2));params.add(new BasicNameValuePair("thirdParam", paramValue3));OutputStream os = conn.getOutputStream();BufferedWriter writer = new BufferedWriter(        new OutputStreamWriter(os, "UTF-8"));writer.write(getQuery(params));writer.flush();writer.close();os.close();conn.connect();

...

private String getQuery(List<NameValuePair> params) throws UnsupportedEncodingException{    StringBuilder result = new StringBuilder();    boolean first = true;    for (NameValuePair pair : params)    {        if (first)            first = false;        else            result.append("&");        result.append(URLEncoder.encode(pair.getName(), "UTF-8"));        result.append("=");        result.append(URLEncoder.encode(pair.getValue(), "UTF-8"));    }    return result.toString();}

Since the NameValuePair is deprecated. Thought of sharing my code

public String  performPostCall(String requestURL,            HashMap<String, String> postDataParams) {        URL url;        String response = "";        try {            url = new URL(requestURL);            HttpURLConnection conn = (HttpURLConnection) url.openConnection();            conn.setReadTimeout(15000);            conn.setConnectTimeout(15000);            conn.setRequestMethod("POST");            conn.setDoInput(true);            conn.setDoOutput(true);            OutputStream os = conn.getOutputStream();            BufferedWriter writer = new BufferedWriter(                    new OutputStreamWriter(os, "UTF-8"));            writer.write(getPostDataString(postDataParams));            writer.flush();            writer.close();            os.close();            int responseCode=conn.getResponseCode();            if (responseCode == HttpsURLConnection.HTTP_OK) {                String line;                BufferedReader br=new BufferedReader(new InputStreamReader(conn.getInputStream()));                while ((line=br.readLine()) != null) {                    response+=line;                }            }            else {                response="";            }        } catch (Exception e) {            e.printStackTrace();        }        return response;    }

....

  private String getPostDataString(HashMap<String, String> params) throws UnsupportedEncodingException{        StringBuilder result = new StringBuilder();        boolean first = true;        for(Map.Entry<String, String> entry : params.entrySet()){            if (first)                first = false;            else                result.append("&");            result.append(URLEncoder.encode(entry.getKey(), "UTF-8"));            result.append("=");            result.append(URLEncoder.encode(entry.getValue(), "UTF-8"));        }        return result.toString();    }

If you don't need the ArrayList<NameValuePair> for parameters, this is a shorter solution that builds the query string using the Uri.Builder class:

URL url = new URL("http://yoururl.com");HttpsURLConnection conn = (HttpsURLConnection) url.openConnection();conn.setReadTimeout(10000);conn.setConnectTimeout(15000);conn.setRequestMethod("POST");conn.setDoInput(true);conn.setDoOutput(true);Uri.Builder builder = new Uri.Builder()        .appendQueryParameter("firstParam", paramValue1)        .appendQueryParameter("secondParam", paramValue2)        .appendQueryParameter("thirdParam", paramValue3);String query = builder.build().getEncodedQuery();OutputStream os = conn.getOutputStream();BufferedWriter writer = new BufferedWriter(            new OutputStreamWriter(os, "UTF-8"));writer.write(query);writer.flush();writer.close();os.close();conn.connect();