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

java.lang.Object
  extended by org.apache.derby.impl.services.cache.Clock
All Implemented Interfaces:
CacheManager, Serviceable

final class Clock
extends java.lang.Object
implements CacheManager, Serviceable

A cache manager that uses a HashMap and an ArrayList. The ArrayList holds CachedItem objects, each with a holder object. The HashMap 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 hash map.

CachedItems can in various state.