using the browser's cache

Anon

With our coding team we ran into an interesting (and tough) problem:

We have banners on our site that our socalled 'redirects'. The url that is provided for the image is not a url that points directly to the image on some server but rather to an ad server that returns the actual url to the image to the browser. Only when this actual url is received by the browser does it load the actual image.

Now our problem is: when we try to reuse that image that was loaded via the redirect url in the same page by setting for example img2.src = img1.src, the browser still starts to reload the second image from the redirect url instead of just using the same image data that it already had for img1. The result is that img2 generally will result in a different graphic because the ad server that is called via the redirect url returns a different image on every request.

So my question is: how can we prevent the browser from reloading the image via the redirect and instead directly use the data that must be somewhere in the browser already?

nightowl

I thought that the browser would use cached-image if the name was identical. unless you press refresh off course.

Anon

In the meantime, I found that in javascript you can use the same image again if you assign the first image to a var. Then you can reuse that var and the same image will appear on the screen. Therefore, with Javascript it's actually not a problem.

In our specific case we have to use the same image, that was loaded via the redirect url, in a java-applet. Then you get firstly the problem of security restrictions because the java applet will not be allowed to access an image from a server that it itself was not downloaded from. Secondly, if we would know how to access the JavaScript data from java we would be done, but we don't know how get the actual data from the browser into the applet.

The strange thing about this problem is, it cannot be much of a security problem, because we're just using the same data as is already in the browser, and the data is already there...

If you know anything about using javascript image data in a java applet, that would be superb.