Re: [ubl-ndrsc] Apache Crimson and W3C XML Schema coverage

["Eve L. Maler" <eve.maler@sun.com>]

In case you're interested, a followup from my colleague Edwin Goei...  When 
I wondered if Xerces 2 was essentially a merge, he provided me with this info.

>Instead of a merge of Xerces 1 and Crimson, I would characterize Xerces
>2 as a re-design which allows different subcomponents to be assembled to
>create a complete parser.  An internal SAX-like API, called XNI (Xerces
>Native Interface) was designed to support this.  The subcomponents
>essentially pass an infoset between each other through XNI.  Examples of
>subcomponents are:
>
>   + xml doc scanner = generates XNI events from input doc
>   + DTD validator
>   + Namespace binder
>   + XML Schema validator
>   + DOM API generator = accepts XNI events and builds DOM
>
>See second diagram under
>http://xml.apache.org/xerces2-j/xni-design.html#pipeline for a nice
>picture.  Most of the current components are either derived from Xerces
>1 code or rewritten from scratch.
>
>In theory because of the more modular design, it should be possible to
>add new components such as a RelaxNG validator or to replace current
>components like the DOM API generator with another implementation.

--
Eve Maler                                    +1 781 442 3190
Sun Microsystems XML Technology Center   eve.maler @ sun.com