docs: @Override
     public void onTag(int fieldNumber, FieldDescriptor fieldDescriptor, Object tagValue) {
        if (payloadStarted) {
           if (skipping == 0) {
              AttributeNode<FieldDescriptor, Integer> attrNode = currentNode.getChild(fieldNumber);
              if (attrNode != null) { // process only 'interesting' tags
                 messageContext.markField(fieldNumber);
                 attrNode.processValue(tagValue, this);
              }
           }
        } else {
           switch (fieldNumber) {
              case WrappedMessage.WRAPPED_DESCRIPTOR_FULL_NAME:
                 entityTypeName = (String) tagValue;
                 break;
  
              case WrappedMessage.WRAPPED_DESCRIPTOR_ID:
                 entityTypeName = serializationContext.getTypeNameById((Integer) tagValue);
                 break;
  
              case WrappedMessage.WRAPPED_MESSAGE:
                 payload = (byte[]) tagValue;
                 break;
  
              case WrappedMessage.WRAPPED_DOUBLE:
              case WrappedMessage.WRAPPED_FLOAT:
              case WrappedMessage.WRAPPED_INT64:
              case WrappedMessage.WRAPPED_UINT64:
              case WrappedMessage.WRAPPED_INT32:
              case WrappedMessage.WRAPPED_FIXED64:
              case WrappedMessage.WRAPPED_FIXED32:
              case WrappedMessage.WRAPPED_BOOL:
              case WrappedMessage.WRAPPED_STRING:
              case WrappedMessage.WRAPPED_BYTES:
              case WrappedMessage.WRAPPED_UINT32:
              case WrappedMessage.WRAPPED_SFIXED32:
              case WrappedMessage.WRAPPED_SFIXED64:
              case WrappedMessage.WRAPPED_SINT32:
              case WrappedMessage.WRAPPED_SINT64:
              case WrappedMessage.WRAPPED_ENUM:
                 break;
              // this is a primitive value, which we ignore for now due to lack of support for querying primitives
  
              default:
                 throw new IllegalStateException("Unexpected field : " + fieldNumber);
           }
        }
     }