Check Web Page Exists Before Redirecting

Hi,

I am a Photographer rather than a we programmer, but I am trying to setup a site where my clients can view their shots.

Essential they type a reference in and it opens a page named that reference .html, I have managed to get the reference enterred and parsed to a susequent page that automatically redirects to the correct reference page.

What I can't fathom is how to check if the page exists before I redirect, this is to catch when they type in an incorrect reference.

Can anyone help ?

What does this have to do with Java?

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