@Override
protected void doPost(HttpServletRequest request, HttpServletResponse response)
        throws ServletException, IOException {
    BufferedReader reader = request.getReader();
    StringBuilder sb = new StringBuilder();
    String line = reader.readLine();
    while (line != null) {
        sb.append(line + "n");
        line = reader.readLine();
    }
    reader.close();
    String data = sb.toString();

    System.out.println(data);
}

JSON jsonObj = JSONObject.fromObject(request.getParameterMap());
System.out.println(jsonObj.toString());

{
   "operation":[
      "V"
   ],
   "phone":[
      "91119"
   ],
   "t":[
      "0FAE2BB0"
   ],
   "numPage":[
      "1"
   ],
   "propertyType":[
      "homes"
   ],
   "locale":[
      "es"
   ],
   "sms":[
      "F"
   ],
   "maxItems":[
      "40"
   ],
   "k":[
      "61AB4"
   ],
   "country":[
      "es"
   ]
}