Hi. I'm using the struts framework to implement a registration system for a University. Is there any way to force a browser refresh when, for example, the number of slots remaining in a class changes? Any help would be greatly appreciated. Thanks.
No. HTTP can't "push", only respond to "pull" requests. About as close as you can get would be to setup a page that has a periodic refresh. Somebody trying to use a page to sign up for courses would find that rather intrusive, however; their data input would be disrupted. If you're thinking about a public display (something like airport flight monitors), then a periodic refresh should be OK.
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