Android - webserver request with JSON response

WebserverRequest.java

package com.xxnoobmanxx.util;

import android.util.Pair;

import org.json.JSONObject;

import java.io.ByteArrayOutputStream;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.UnsupportedEncodingException;
import java.net.HttpURLConnection;
import java.net.URL;
import java.util.ArrayList;
import java.util.List;

/**
 * Created by carucce on 17/11/2015.
 */
public final class WebserverRequest {

    public final static String CHARSET = "UTF8";

    /**
     *
     * @param address
     * @return
     */
    public static JSONObject send(String address){
        List<Pair<String,String>> params = new ArrayList<Pair<String, String>>();
        return send(address, params);
    }

    /**
     *
     * @param address
     * @param params
     * @return
     */
    public static JSONObject send(String address, List<Pair<String,String>> params){

        JSONObject response = null;

        try {

            URL url = new URL(address);
            HttpURLConnection connection = (HttpURLConnection) url.openConnection();
            connection.setConnectTimeout(3000);
            connection.setReadTimeout(3000);
            connection.setDoOutput(true);
            connection.setRequestMethod("POST");
            connection.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");
            connection.connect();

            OutputStream outputStream = connection.getOutputStream();
            outputStream.write(getQueryBytes(params));
            outputStream.flush();
            outputStream.close();

            if(connection.getResponseCode() == HttpURLConnection.HTTP_OK){

                InputStream inputStream = connection.getInputStream();

                ByteArrayOutputStream byteArrayOutputStream  = new ByteArrayOutputStream ();
                byte[] buffer = new byte[1024];
                int len;
                while ((len = inputStream.read(buffer)) > 0){
                    byteArrayOutputStream.write(buffer,  0, len);
                }
                byte[] responseBytes = byteArrayOutputStream.toByteArray();

                byteArrayOutputStream.close();
                inputStream.close();

                String responseString = new String(responseBytes);
                response = new JSONObject(responseString);

            }

        }catch (Exception e) {
            e.printStackTrace();
        }

        return response;

    }

    /**
     *
     * @param params
     * @return
     * @throws UnsupportedEncodingException
     */
    private static byte[] getQueryBytes(List<Pair<String,String>> params) throws UnsupportedEncodingException {

        StringBuffer buffer = new StringBuffer();
        for(Pair<String,String> pair : params){
            String first = URLEncoder.encode(pair.first, CHARSET);
            String second = URLEncoder.encode(pair.second, CHARSET);
            buffer.append(first + "=" + second + "&");
        }
        String finalString = buffer.toString();
        finalString = (finalString.length() > 0 ? finalString.substring(0, finalString.length() - 1) : "");
        return finalString.getBytes(CHARSET);

    }

}