docs: public Map<String, Class<?>> getPayloadPropertyNames(Map<String,Class<?>> mapPropertyNames)
      {
          mapPropertyNames= super.getPayloadPropertyNames(mapPropertyNames);
          if (m_messageDataDescChildren != null)
          {
              for (String strKey : m_messageDataDescChildren.keySet())
              {
                  MessageDataDesc messageDataDesc = m_messageDataDescChildren.get(strKey);
                  mapPropertyNames = messageDataDesc.getPayloadPropertyNames(mapPropertyNames);
              }
          }
          return mapPropertyNames;
      }