A generic class to represent the cache related infomation of a cached object (Cacheable).
The relationship between isValid and settingIdentity can be explain by the
following life cycle of a cached item.
Stage 1 2 3
----------------------
isValid F T T
settingIdentity X T F
In Stage 1, the CachedItem is created but it is invalid and has an entry
that is just a holder object with no identity.
In Stage 2, the identity has been set and the item is being created or
being faulted into the cache.
In Stage 3, the item found in the CachedItem entry
Remove is set if this item is being removed out of existance, not just
being evicted from the cache. |