URL versus relative path schemaLocation imports

Hi,

We have a large number of XML schemas and have separated some of these into
common schemas that we reuse using the xsd import element.

e.g. 
<xsd:import namespace="http://...." schemaLocation="...."/>

I was wondering if there are any best practices for choosing URL
(http://....) over a relative path (../../schema.xsd). Any references to
documentation or discussions would be great.

Using a HTTP URL requires that we host these schemas on a web server and that
imposes a runtime dependency for us as our implementation technology (JAXB)
requires that we validate against these schemas at runtime. 

Thanks,
Paul Ryan.


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