code: public String getQueryString(){
          StringBuilder sb = new StringBuilder();
          for (Entry<String, Object> parameter : parameters.entrySet()){
              if (sb.length() > 0){
                  sb.append("&");
              }
              sb.append(parameter.getKey());
              sb.append("=");
              sb.append(parameter.getValue().toString());
          }
          for (Entry<String, List> customTrackingParameter : customTrackingParameters.entrySet()){
              for (Object o : customTrackingParameter.getValue()){
                  if (sb.length() > 0){
                      sb.append("&");
                  }
                  sb.append(customTrackingParameter.getKey());
                  sb.append("=");
                  sb.append(o.toString());
              }
          }
          
          return sb.toString();
      }
docs: Get the query string represented by this object.
  @return the query string represented by this object