sed.<DD><CODE>urlConnectionExpiryCalculator</CODE> - the calculator object for heuristic
 calculation of the resource expiry, used when no expiry is provided by 
 the server of the resource. Can be null, in which case the maximum age
 of cached entries without validation will be zero.<DD><CODE>urlConnectionSecurityDomainProvider</CODE> - object that provides security
 domain objects for the loaded sources. Can be null, in which case the
 loaded sources will have no security domain associated with them.</DL>