org.apache.derby.impl.services.cache
Class Clock

java.lang.Object
  extended byjava.util.Dictionary
      extended byjava.util.Hashtable
          extended byorg.apache.derby.impl.services.cache.Clock
All Implemented Interfaces:
CacheManager, java.lang.Cloneable, java.util.Map, java.io.Serializable, Serviceable

final class Clock
extends java.util.Hashtable
implements CacheManager, Serviceable

A cache manager that uses a Hashtable and a ArrayList. The ArrayList holds CachedItem objects, each with a holder object. The Hashtable is keyed by the identity of the holder object (Cacheable.getIdentity()) and the data portion is a pointer to the CachedItem. CachedItems that have holder objects with no identity do not have entries in the hashtable.

CachedItems can in various state.