/// <summary>
/// lookup or store an object in the 'live object cache'.
/// Example:
/// To store Product with ProductID=1, we use the following IdentityKey:
/// IdentityKey{Type=Product, Keys={1}}
/// </summary>
/// <param name="key"></param>
/// <returns></returns>
public object this[IdentityKey key]
{
get
{
object o;
lock (entities)
entities.TryGetValue(key, out o);
return o;
}
set
{
lock (entities)
entities[key] = value;
}
}
/// <summary>
/// Registers an entity to be watched
/// </summary>
/// <param name="entity"></param>
/// <param name="identityKey"></param>
public void RegisterToWatch(object entity, IdentityKey identityKey)
{
}
/// <summary>
/// Finds entity by key (PK)
/// </summary>
/// <param name="identityKey"></param>
/// <returns></returns>
public EntityTrack FindByIdentity(IdentityKey identityKey)
{
return null;
}
/// <summary>
/// Finds entity by key (PK)
/// </summary>
/// <param name="identityKey"></param>
/// <returns></returns>
public EntityTrack FindByIdentity(IdentityKey identityKey)
{
EntityTrack entityTrack;
entitiesByKey.TryGetValue(identityKey, out entityTrack);
return entityTrack;
}
/// <summary>
/// Registers an entity to be watched
/// </summary>
/// <param name="entity"></param>
/// <param name="identityKey"></param>
public void RegisterToWatch(object entity, IdentityKey identityKey)
{
var entityTrack = FindByReference(entity);
if (entityTrack == null)
{
entityTrack = FindByIdentity(identityKey);
if (entityTrack != null)
throw new System.Data.Linq.DuplicateKeyException(entity);
entityTrack = new EntityTrack(entity, EntityState.ToWatch) { IdentityKey = identityKey };
entities.Add(entityTrack);
entitiesByKey[identityKey] = entityTrack;
}
else
{
// changes the state of the current entity
switch (entityTrack.EntityState)
{
case EntityState.ToInsert:
entityTrack.EntityState = EntityState.ToWatch;
entityTrack.IdentityKey = identityKey;
entitiesByKey[identityKey] = entityTrack;
break;
// watched entities should not be registered again
case EntityState.ToWatch:
case EntityState.ToDelete:
throw new InvalidOperationException();
default:
throw new ArgumentOutOfRangeException();
}
}
}
public void Remove(IdentityKey key)
{
lock (entities)
entities.Remove(key);
}
