I have a picture on a given URL. The picture might need a referesh. I want to do the freshness-check at the time of the request. Therefore, I coded a jersey resource handling the request on the picture URL. It refreshes the picture on the filesystem if necessary. I do not want to re-code a caching mechansim, but rely on tomcat's implementation. Therefore, I would like to "forward" the request in the internal handler chain. I tried return new Viewable(sb.toString());, but a viewable is not a picture. What return type can I use?

I could let the concrete picture reside on another URL and send a 307 (Temporary Redirect). Always sending that as answer seems odd to me.

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