Prefixing CDN URL to resources base path

Hi,
I'm trying to make the use of CDN hassle free with my Wicket Apps.
.. where *IF* a CDN location is specified then all paths like

.. become

This applies to JS, CSS, and img tags mainly.

Am wondering where the best place to automate this would be ?
1. Build Process; do a REPLACE during production BUILD
2. Wicket code that loads using IResourceStream UrlResourceStream(url) ;
Intercept the raw HTML stream and re-generate it? (if this is cached may be
efficient??)
3. HttpServletFilter --> Just before its passed back from the Web Server. Do
a RegEx scan and replace (Maybe too inefficient , but less intrusive to any
Wicket Vodoo)

Thoughts?

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