Re: Validating against a Schema

[Eric van der Vlist <vdv@dyomedea.com>]

Richard Featherstone wrote:
> 
> Could someone either tell me how or point me in the right direction to
> find out how to validate an XML doc against a Schema using Java.  I can
> parse without validating but don't know
> 
> a) how the parser can decide what Schema is being used from the XML doc
> and where to locate it

First thing, you need to use a XML parser that supports W3C XML Schema
such as Xerces-J [1] (1.4.1 or above) .

Then, the parser will have 3 ways to locate the schema to use.

1) Parsers are required to provide an implementation specific way to
define the schema locations as parameters.

Xerces-J does this through the                
http://apache.org/xml/properties/schema/external-schemaLocation and
http://apache.org/xml/properties/schema/external-noNamespaceSchemaLocation
properties.

2) Using the xsi:schemaLocation and xsi:noNamespaceSchemaLocation
attributes in the instance document.

3) Trying to dereference the URI associated with the namespace to see if
there is a schema at this location.
 
> 
> b) how to configure the parser to validate the doc against the schema

Using the "isValidating" method.
 
> I apologise if this is the wrong place to ask a question like this but
> I've spent days looking everywhere for the answer.

You should have asked before ;=)

Hope this helps.

Eric

[1] http://xml.apache.org/xerces-j/index.html

> 
> thanks in advance
> 
> Richard
> 
-- 
See you at XTech in San Diego.
             http://conferences.oreillynet.com/cs/os2001/view/e_spkr/790
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Eric van der Vlist       http://xmlfr.org            http://dyomedea.com
http://xsltunit.org      http://4xt.org           http://examplotron.org
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