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XML-Java-database interoperability tool provides full XML Schema support

From: Jeff <jeff@cogentlogic.com>
Date: Thu, 30 May 2002 16:20:24 -0400
To: <xmlschema-dev@w3.org>, <cmsmcq@w3.org>
Message-ID: <NBBBIEJICNNKIJDKIOMJOEIAEAAA.jeff@cogentlogic.com>

In accordance with the invitation at http://www.w3.org/XML/Schema#Tools, I
am submitting details of a new software development tool that makes XML
Schema a cinch for Java developers: no SAX, no DOM, no JDBC, just data as
Java objects. Major benefit: dramatic reduction in development time.

XchainJ Developer is a GUI-based tool that reads any number of
included/imported/redefined XML Schema documents and DTDs (using XML Catalog
for URI resolution) and presents the resultant integrated XML Schema using a
terse syntax. Java bindings are automatically generated and much of the XML
Schema structure (that doesn't appear explicitly in XML instances) is
stripped away. The Java bindings contain only data (though user-specified
code could be added, if desired). Transformations between XML, Java and
databases are performed by invoking single instructions against the XchainJ
Processor once it has been configured with mapping files exported from
XchainJ Developer. Thus, Java developers can read/write XML and databases
using simple code and the data appears as Java objects.

Why interpose Java? When mapping XML to databases there are two problems
that need to be solved. Firstly, XML is hierarchical and databases are
almost 'flat'. Secondly, data formats in databases are often different to
those in XML, dates, for example, might need reformatting and sometime
several database columns map to one element. The default Java bindings
exactly reflect the XML hierarchy (elements and complex types mapping to
classes)  but they are soon 'flattened' in a simple process we call
'SQLching' (preparing for SQL, pronounced "squelching"). SQLching also
serves to eliminate much of the complexity of XML Schema: simple/complex
types, restrictions, groups, etc., etc. are great for architects but only
impede programmers (they don't show up in the XML, though they do influence
the XML). Interposing Java between XML and databases also enables unlimited
processing to occur to fix up disparities between XML and database data but
also for calculations and any other desired business logic. This design is,
for Java developers, exceedingly powerful. Since the coding involved is
often trivial, required Java skills are minimal.

XchainJ 1.0 has been in production at various Government of Canada locations
since January 2002 but it only supports DTDs

XchainJ 1.1 was launched last week at XML Europe 2002 and provides full
support for XML Schema. An evaluation version is available for download from
www.XchainJ.com. At the conference in Barcelona I was able to demonstrate
the XML Schema capabilities of XchainJ to a W3C representative, who
coincidentally lives in Toronto. He was impressed :-)

You may like to check out the Geography Markup Language (GML) 2.0 and Dublin
Core Metadata Initiative (DCMI) application guides at www.XchainJ.com for
in-depth treatment of XML Schema including 'round-trip' demonstrations and
extensive use of substitution groups. (An FGDC-based application guide
showing database interoperability is due soon.)

I shall be grateful if XchainJ could be listed at
http://www.w3.org/XML/Schema#Tools. Thank you.

Warmest regards,

Jeff Lawson
Cogent Logic Corporation
Toronto, Canada
+1 (416) 340 8025

Received on Thursday, 30 May 2002 16:20:24 UTC

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