code: @Override
    public ITextNode getTextNode(String key) {
      for (ITextNode node : textNodeList) {
        if (key.equals(node.getKey())) {
          return node;
        }
      }
      return null;
    }
docs: Gets the text node for a given key.
  @param key the key of the text node to get
  @return the text node for the given key or <code>null</code> if
  no text node exists for the given key.