Ways to force a page refresh?

[Dave Boland]

I'm doing some work on a data acquisition system for
temperature sensors. The displayed readings don't change
much over time, so what I would like to do is to force a
page refresh only when the data changes by 5% or more, or
when the temperature is over a limit.

So far my options seem to be frequent page refreshes using a
meta tag, or using Java. The meta tags are a fixed time
interval and may be too frequent (or not frequent enough),
and the Java may be a problem because some companies have
some strict Java rules to security. Any other ideas?

Thanks,
Dave

 

[J.O. Aho]

I'm doing some work on a data acquisition system for temperature
sensors. The displayed readings don't change much over time, so what I
would like to do is to force a page refresh only when the data changes
by 5% or more, or when the temperature is over a limit.

JavaApplet, see
http://java.sun.com/docs/books/tutorial/uiswing/components/applet.html

So far my options seem to be frequent page refreshes using a meta tag,
or using Java.

I think you mean JavaScript, which isn't at all the same thing as Java.
See this article: http://www.htmlgoodies.com/beyond/javascript/article.php/3470971

The meta tags are a fixed time interval and may be too
frequent (or not frequent enough)

The only way to make HTML to load a page is to let an user load a page or use
meta tag to reload in an interval, or send a http-header that tells the
browser to reload the page after a time interval or use javascript to count
down time to force the browser to reload the page.

A server can't just send a page to someone without request (of course it
could, but no browser would get the data).