code: @Override
  	public final TableTreeNode getNodeAtLine(final int row) {
  		TableTreeNode node = root.next(); // the root node is never used
  
  		for (int index = 0; node != null && index < row; index++) {
  			node = node.next();
  		}
  
  		return node;
  	}
docs: Returns the node at the given line.
  
  @param row the row index.
  @return the node at the given line, or null if the index is out of bounds.