code: @Override
      protected void emitStartElement(final INodeReadTrx rtx) throws TTIOException {
          switch (rtx.getNode().getKind()) {
          case ROOT:
              break;
          case ELEMENT:
              generateElement(rtx);
              break;
          case TEXT:
              generateText(rtx);
              break;
          default:
              throw new UnsupportedOperationException("Node kind not supported by Treetank!");
          }
      }
docs: {@inheritDoc}
  
  @throws TTIOException