> Instead have put in chapter 3 "Software
Engineering" a summary of various
> methodologies used in practise for developing DTDs.
-----Original
Message-----
From: Rick Jelliffe <ricko@allette.com.au>
To:
XML Mail List <xml-dev@ic.ac.uk>
Date:
Sunday, July 12, 1998 5:28 PM
Subject: RE: Merging Object
Oriented Design and SGML Architectures
The big fat Cue book (I think it is called "Using
SGML") has a chapter relating Smalltalk to
SGML.
Steve Newcomb has pointed out (reference lost-sorry) that
SGML/XML and OO to a large extent have dissimilar goals, in that
SGML/XML (i.e. generic markup) are attempts to (allow you to) have your
data INDEPENDENT of particular methods while OO is an attempt to bundle
methods with data. However, since the introduction of the PI
target in XML, it is better to say that SGML/XML are attempts to (allow
you to) have your data in a form which allows multiple methods to be
attached.
The big fat Holzer book (I think it is called "XML
Complete") is full of code and analysis relating Java to XML. (But
the reviews on amazon.com suggest that it may relate to a superceded
version of MSXML too much.)
In a sense, a lot of the questions about OO and XML may already
be answered, in that XML/SGML embody a particular document system design
methodology (i.e. generalized markup) and because common parsers will be
using three APIs:
* SAX, which XML-DEV contributed
to
* GROVES: this is the big daddy of
them all, and is not so much an API as an analysis of the properties
needed for a complete and general SGML/XML/HyTime "parse
tree". (In fact any data format whcih can be parsed into a tree
with inter-node directed-graph arcs can be represented by GROVE, e.g.
CGM the graphics format. Using the same GROVE concept allows navigation
languages like Xptr to be defined that can locate particular nodes in
the tree, regardless of what notation the tree was parsed from.) The
GROVES information is at http://www.ornl.gov/sgml/wg8/docs/n1920/html/clause-7.1.html#clause-7.1.4
might be useful place to start.
My big fat book, The XML and SGML Cookbook, does not have much OO
in it (intentionally: there is no progamming code in it). Instead have
put in chapter 3 "Software Engineering" a summary of
various methodologies used in practise for developing DTDs. This is
because once you have the generalized model OK, you can add methods
(explicitly by using #FIXED attributes in the DTD, or by invoking a
CSS-like stylesheet where there is an element type to contain mthod code
or location, or by using PIs.) So the emphasis is that the
more richly and appropriately your data is marked up, the less
programming work (including OO analysis and design) there is to
do.
There is a widespread feeling in the SGML world that you should
mark up data independent of any particular use of it. However, I
certainly believe that a good DTD design will be informed by the known
and potential uses of the data. In a way it comes down to whether you
view XML as a "serialization format" format, where it is just
dumping data from a known schema and known application, or whether it is
"markup language" where you want to expose interesting and
useful information to make life simpler for future software
development.
Rick Jelliffe
Hello,
Could anyone please guide to articles/technical notes regarding OOD
and SGML Architectures.
Any help will be greatly appreciated
Thanx,
AMIT
