/**
* This cached entry needs revalidation, it will modify the
* request to do that.
*/
public Request setRequestRevalidation(Request request) {
Request origreq = (Request) request.getClone();
request.setState(CacheState.STATE_RESOURCE, this);
request.setState(CacheState.STATE_ORIGREQ, origreq);
// At this point, we use the suggested way of using date as etag:
request.setIfModifiedSince(getLastModified());
// But if we do have an etag, we also uses it, as recommended: