|Object||getResource () throws ResourceException|
|long||getVersion (ResourceKey key)|
A resource is a wrapper around the final product. It shall not hold any references to the ResourceData object used to create the resource (to allow efficient 2-stage caching).
Although this interfaces declares to be serializable, this might not be the case for some of the content contained in the resource object. Cache implementors should be aware of that issue and should act accordingly (for instance by not caching that object).