RE: [xml-dev] reasons why an XML instance must be validated with a XML s

["Michael Kay" <mike@saxonica.com>]

XML schema actually does more than validation: it can also annotate and augment the document with type information, making it easier to process.

 

But if validation is your concern, it's the general principle of software engineering: software components should define their interfaces and at least be capable of failing cleanly if the constraints on the interface are not satisfied.

 

If you have full trust between the components either side of an interface then validation may be unnecessary. But experience suggests that if you trust another piece of software to do the right thing then eventually you will find your trust is misplaced.

 

Michael Kay

http://www.saxonica.com/

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From: ilango [mailto:ilangocal@yahoo.com]
Sent: 09 September 2008 16:05
To: xml-dev@lists.xml.org
Subject: [xml-dev] reasons why an XML instance must be validated with a XML schema

I just started working on a project that uses JMS/WebSphere MQ with non-J2EE systems to build an enterprise system. We would be using XML for all the request/response message flows that take place between two system (for example, a JMS Listener and one or more than one queues.

I was posed with the following scenario: Our Listener Module submits document requests in XML formatted data into an input message queue monitored by a document generaton engine.
The need for validating the XML naturally arises.  Should the XML be validated against an XML schema.
The question they raised was:
If so, why should we use XML schema to validate XML?

So this is the question I am trying to answer for myself and for my team here.

Any suggestions, ideas are gratefully accepted.

thanks
ilango