/// <summary>
/// Locates an entity for retrieval from the <see cref="EntityLocator"/> if tracking is enabled.
/// </summary>
/// <typeparam name="TEntity">Must implement <see cref="IEntity"/> and is the default type to create, and will be the return type.</typeparam>
/// <param name="key">primary key representation</param>
/// <param name="isLocatorEnabled">bool determining whether to use Entity Locating.</param>
/// <returns>found entity of T, or null</returns>
public static TEntity LocateEntity <TEntity>(string key, bool isLocatorEnabled) where TEntity : class, IEntity, new()
{
TEntity entity = null;
//attempt to locate
if (key != null && isLocatorEnabled)
{
lock (syncObject)
{
if (EntityLocator.Contains(key))
{
entity = EntityLocator.Get(key) as TEntity;
}
}
}
return(entity);
}
/// <summary>
/// Locates an entity for retrieval from the <see cref="EntityLocator"/>, or instatiates a new instance
/// of the entity if not currently being tracked.
/// </summary>
/// <typeparam name="TEntity">Must implement <see cref="IEntity"/> and is the default type to create, and will be the return type.</typeparam>
/// <param name="key">primary key representation</param>
/// <param name="typeString">type string to create</param>
/// <param name="entityFactoryType">factory used to try to create this entity.</param>
/// <param name="isLocatorEnabled">bool determining whether to use Entity Locating.</param>
/// <returns>Created entity of T</returns>
public static TEntity LocateOrCreate <TEntity>(string key, string typeString, Type entityFactoryType, bool isLocatorEnabled) where TEntity : class, IEntity, new()
{
#region Validation
if (string.IsNullOrEmpty(typeString))
{
throw new ArgumentException("typeString");
}
if (entityFactoryType == null)
{
throw new ArgumentException("entityFactoryType");
}
#endregion
TEntity entity = default(TEntity);
lock (syncObject) //This is here because most of the classes in ObjectBuilder are NOT thread-safe
{
//Generated Table Entities Type
Type defaultType = typeof(TEntity);
bool isCacheable = defaultType.GetInterface("IEntityCacheItem") != null;
//see if entity is cachable, if IEntityCacheItem
//retrieve from cache.
if (isCacheable)
{
entity = EntityCache.GetItem <TEntity>(key.ToString());
}
if (entity != null)
{
return(entity);
}
IEntityFactory factory = null;
lock (syncObject)
{
if (EntityFactories.ContainsKey(entityFactoryType.FullName))
{
factory = EntityFactories[entityFactoryType.FullName];
}
else
{
factory = TryAddEntityFactory(entityFactoryType);
}
}
//attempt to locate
if (key != null && isLocatorEnabled)
{
lock (syncObject)
{
if (EntityLocator.Contains(key))
{
entity = EntityLocator.Get(key) as TEntity;
}
}
}
//if not found try create from factory
if (entity == null)
{
entity = factory.CreateEntity(typeString, defaultType) as TEntity;
}
//add to locator and start tracking.
if (!entity.IsEntityTracked)
{
StartTracking(key, entity, isLocatorEnabled);
}
//add entity to Cache if IEntityCacheItem
if (entity.GetType().GetInterface("IEntityCacheItem") != null)
{
EntityCache.AddCache(key, entity);
}
}
return(entity);
}