I want to validate updates to a document made via XUpdate.

    At this point, I primarily wish to remove the ignorable white
    space from the updated document as it is updated.

    I have no experience with validation. I'm assuming that it is
    possible to validate an individual node using one of existing
    Schema engines, but I have no idea where to start.

    There are two methods to pursue.

    1) Create an XML Schema for XUpdate, use nested XML Schemas.

        If this removes whitespace, and validates the XUpdate
        statement, I can then insert the result.

        There are some use cases of XUpdate, inserting a text node,
        where I am certian you need to look at the result.

    2) Use a validation API that answers the question, "is this
        node, given this parsed schema, valid it it's current
        context?" This seems to be called "partial validation". 

    If I pursue 1) then I'll have to learn a lot of new things
    before I can strip that whitespace. (It seems like I'll be
    hacking XML Schema for every update statement.)

    If I pursue 2) I'll be able to swap out schema implementations.

    I'm reading through javax.xml.validation for a crack at 2).

    It seems to take a node and validate all the children. I'm not
    sure if this is what I want. If I add an attribute to the root
    node of a large document, I don't need to validate the entire
    document, just the attributes of the newly modified node.

    And insight is appreciated.

    Cheers.

--
Alan Gutierrez - alan@e...
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