docs: public Map<String,Object> getPayloadProperties(Object msg, Map<String,Class<?>> mapPropertyNames)
      {
          Map<String,Object> properties = new HashMap<String,Object>();
          
          for (String strKey : mapPropertyNames.keySet())
          {
              this.addPayloadProperty(msg, properties, strKey);            
          }
          this.addPayloadProperty(msg, properties, "Errors"); // For responses only            
          return properties;
      }