August 30, 2005

Baby Report: JDOM code for appending Lawrence

Follow-up to Baby Report: The latest photos of Lawrence from Transversality - Robert O'Toole

I've been doing lots of work with the JDOM Java xml parser. The result is as follows:

Element robert = reality.getRootElement();
Element lawrence = new Element("Lawrence");
robert.appendChild(lawrence);

However, if I try the following:

Element robert = reality.getRootElement().getChild("robert");
Element emma = reality.getRootElement().getChild("emma")
Element lawrence = new Element("Lawrence");
robert.appendChild(lawrence);
emma.appendChild(lawrence);

I get a nasty error message stating that the element lawrence cannot be appended to more than one parent element. Does XML only support single parent families? Should i be doing something tricky with XLink? Help!


Robert O'Toole : 30 Aug 2005 16:15 |  Tags:        |  Comments (5) |  Report a problem

- 5 comments by 3 or more people Not publicly viewable

  1. Chris May

    Does XML only support single parent families?

    Sadly yes. Single-parent family trees, anyway. I blame those degenerates at the W3C. ;-)

    Fortunately, upstanding members of the community can get round it by introducing a relationship element, linking person elements by ID, a la FOAF. RDF is the cannonical example of adapting XML to handle many-to-many relationships effectively.

    In answer to your last question, no you shouldn't be doing something tricky with XLink, you should be changing nappies, or possibly making a nice hot drink for Emma.

    30 Aug 2005, 22:20

  2. Joseph

    You need to create a root 'family' node, then you can have as many parents and children as you want, but beware of compatibilty conflicts… ¦:¬)*)

    31 Aug 2005, 09:57

  3. Robert O'Toole

    Chris, that's very phenomenological: two documents, each containing there own seperate 'reality' elements, but somehow joined through the void by a meta-linking act of epoche.

    10 Sep 2005, 10:31

  4. Chris May

    I thought epoche was a state (specifically, a state of being-in-the-world, of existing without causing, waiting for some external force to determine one's path). What's an 'act of epoche?'

    You mean phenomenology in the sense of Husserl / Heidegger I take it, and not in the physics sense of 'making a bit of a guess, which seems right but isn't directly modelled by theory, because the theory isn't sophisticated enough yet ' :-).
    I actually think that in this case the latter is a better description: The model (XML) just isn't well suited to to expressing an nn relationship without vague hand-wavy ID relationships that 'join through the void' :-)

    12 Sep 2005, 20:16

  5. I'm just not clever enough to understand any of this :)

    07 Oct 2005, 16:16

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