XOM API for Processing XML with Java

["McEniry, Michael" <mmceniry AT itsc.uah.edu>]

The node hierarchy does not prevent cycles 
(aka "I'm my own grandpa").

The simplest example is:

  Element a = new Element("a");
  a.appendChild(a);
  // time passes...
  a.toXML(); // causes a StackOverflowError

In my case, it was a dumb typo, but the error appears 
far away from the typo, and I consumed what few sanity 
points I had left tracking this down.

Should ParentNode.insertChild(Node child, int position) 
climb its own parent tree looking for child?

  ...
  for (ParentNode parent = this; 
       parent != null; 
       parent = parent.getParent()) {
    if (parent == child) {
      throw new SomeException("cyclic hierarchy");
    }
  }
  ...

Has this been discussed before? If so, please, 
point me there. Thanks.