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//---------------------------------------------------------------------
// <copyright file="EntityWrapper.cs" company="Microsoft">
// Copyright (c) Microsoft Corporation. All rights reserved.
// </copyright>
//
// @owner Microsoft
// @backupOwner Microsoft
//---------------------------------------------------------------------
using System.Collections;
using System.Data.Objects.DataClasses;
using System.Diagnostics;
using System.Reflection;
using System.Data.Metadata.Edm;
namespace System.Data.Objects.Internal
{
/// <summary>
/// An extension of the EntityWrapper class for entities that are known not to implement
/// IEntityWithRelationships. Using this class causes the RelationshipManager to be created
/// independently.
/// </summary>
/// <typeparam name="TEntity">The type of entity wrapped</typeparam>
internal sealed class EntityWrapperWithoutRelationships<TEntity> : EntityWrapper<TEntity>
{
/// <summary>
/// Constructs a wrapper as part of the materialization process. This constructor is only used
/// during materialization where it is known that the entity being wrapped is newly constructed.
/// This means that some checks are not performed that might be needed when thw wrapper is
/// created at other times, and information such as the identity type is passed in because
/// it is readily available in the materializer.
/// </summary>
/// <param name="entity">The entity to wrap</param>
/// <param name="key">The entity's key</param>
/// <param name="entitySet">The entity set, or null if none is known</param>
/// <param name="context">The context to which the entity should be attached</param>
/// <param name="mergeOption">NoTracking for non-tracked entities, AppendOnly otherwise</param>
/// <param name="identityType">The type of the entity ignoring any possible proxy type</param>
/// <param name="propertyStrategy">A delegate to create the property accesor strategy object</param>
/// <param name="changeTrackingStrategy">A delegate to create the change tracking strategy object</param>
/// <param name="keyStrategy">A delegate to create the entity key strategy object</param>
internal EntityWrapperWithoutRelationships(TEntity entity, EntityKey key, EntitySet entitySet, ObjectContext context, MergeOption mergeOption, Type identityType,
Func<object, IPropertyAccessorStrategy> propertyStrategy, Func<object, IChangeTrackingStrategy> changeTrackingStrategy, Func<object, IEntityKeyStrategy> keyStrategy)
: base(entity, RelationshipManager.Create(), key, entitySet, context, mergeOption, identityType,
propertyStrategy, changeTrackingStrategy, keyStrategy)
{
}
/// <summary>
/// Constructs a wrapper for the given entity.
/// Note: use EntityWrapperFactory instead of calling this constructor directly.
/// </summary>
/// <param name="entity">The entity to wrap</param>
/// <param name="propertyStrategy">A delegate to create the property accesor strategy object</param>
/// <param name="changeTrackingStrategy">A delegate to create the change tracking strategy object</param>
/// <param name="keyStrategy">A delegate to create the entity key strategy object</param>
internal EntityWrapperWithoutRelationships(TEntity entity, Func<object, IPropertyAccessorStrategy> propertyStrategy, Func<object, IChangeTrackingStrategy> changeTrackingStrategy, Func<object, IEntityKeyStrategy> keyStrategy)
: base(entity, RelationshipManager.Create(), propertyStrategy, changeTrackingStrategy, keyStrategy)
{
}
public override bool OwnsRelationshipManager
{
get { return false; }
}
public override void TakeSnapshotOfRelationships(EntityEntry entry)
{
entry.TakeSnapshotOfRelationships();
}
// See IEntityWrapper documentation
public override bool RequiresRelationshipChangeTracking
{
get { return true; }
}
}
/// <summary>
/// An extension of the EntityWrapper class for entities that implement IEntityWithRelationships.
/// Using this class causes creation of the RelationshipManager to be defered to the entity object.
/// </summary>
/// <typeparam name="TEntity">The type of entity wrapped</typeparam>
internal sealed class EntityWrapperWithRelationships<TEntity> : EntityWrapper<TEntity>
where TEntity : IEntityWithRelationships
{
/// <summary>
/// Constructs a wrapper as part of the materialization process. This constructor is only used
/// during materialization where it is known that the entity being wrapped is newly constructed.
/// This means that some checks are not performed that might be needed when thw wrapper is
/// created at other times, and information such as the identity type is passed in because
/// it is readily available in the materializer.
/// </summary>
/// <param name="entity">The entity to wrap</param>
/// <param name="key">The entity's key</param>
/// <param name="entitySet">The entity set, or null if none is known</param>
/// <param name="context">The context to which the entity should be attached</param>
/// <param name="mergeOption">NoTracking for non-tracked entities, AppendOnly otherwise</param>
/// <param name="identityType">The type of the entity ignoring any possible proxy type</param>
/// <param name="propertyStrategy">A delegate to create the property accesor strategy object</param>
/// <param name="changeTrackingStrategy">A delegate to create the change tracking strategy object</param>
/// <param name="keyStrategy">A delegate to create the entity key strategy object</param>
internal EntityWrapperWithRelationships(TEntity entity, EntityKey key, EntitySet entitySet, ObjectContext context, MergeOption mergeOption, Type identityType,
Func<object, IPropertyAccessorStrategy> propertyStrategy, Func<object, IChangeTrackingStrategy> changeTrackingStrategy, Func<object, IEntityKeyStrategy> keyStrategy)
: base(entity, entity.RelationshipManager, key, entitySet, context, mergeOption, identityType,
propertyStrategy, changeTrackingStrategy, keyStrategy)
{
}
/// <summary>
/// Constructs a wrapper for the given entity.
/// Note: use EntityWrapperFactory instead of calling this constructor directly.
/// </summary>
/// <param name="entity">The entity to wrap</param>
/// <param name="propertyStrategy">A delegate to create the property accesor strategy object</param>
/// <param name="changeTrackingStrategy">A delegate to create the change tracking strategy object</param>
/// <param name="keyStrategy">A delegate to create the entity key strategy object</param>
internal EntityWrapperWithRelationships(TEntity entity, Func<object, IPropertyAccessorStrategy> propertyStrategy, Func<object, IChangeTrackingStrategy> changeTrackingStrategy, Func<object, IEntityKeyStrategy> keyStrategy)
: base(entity, entity.RelationshipManager, propertyStrategy, changeTrackingStrategy, keyStrategy)
{
}
public override bool OwnsRelationshipManager
{
get { return true; }
}
public override void TakeSnapshotOfRelationships(EntityEntry entry)
{
}
// See IEntityWrapper documentation
public override bool RequiresRelationshipChangeTracking
{
get { return false; }
}
}
/// <summary>
/// Implementation of the IEntityWrapper interface that is used for non-null entities that do not implement
/// all of our standard interfaces: IEntityWithKey, IEntityWithRelationships, and IEntityWithChangeTracker, and
/// are not proxies.
/// Different strategies for dealing with these entities are defined by strategy objects that are set into the
/// wrapper at constructionn time.
/// </summary>
internal abstract class EntityWrapper<TEntity> : BaseEntityWrapper<TEntity>
{
private readonly TEntity _entity;
private IPropertyAccessorStrategy _propertyStrategy;
private IChangeTrackingStrategy _changeTrackingStrategy;
private IEntityKeyStrategy _keyStrategy;
/// <summary>
/// Constructs a wrapper for the given entity.
/// Note: use EntityWrapperFactory instead of calling this constructor directly.
/// </summary>
/// <param name="entity">The entity to wrap</param>
/// <param name="relationshipManager">The RelationshipManager associated with the entity</param>
/// <param name="propertyStrategy">A delegate to create the property accesor strategy object</param>
/// <param name="changeTrackingStrategy">A delegate to create the change tracking strategy object</param>
/// <param name="keyStrategy">A delegate to create the entity key strategy object</param>
protected EntityWrapper(TEntity entity, RelationshipManager relationshipManager,
Func<object, IPropertyAccessorStrategy> propertyStrategy, Func<object, IChangeTrackingStrategy> changeTrackingStrategy, Func<object, IEntityKeyStrategy> keyStrategy)
: base(entity, relationshipManager)
{
if (relationshipManager == null)
{
throw EntityUtil.UnexpectedNullRelationshipManager();
}
_entity = entity;
_propertyStrategy = propertyStrategy(entity);
_changeTrackingStrategy = changeTrackingStrategy(entity);
_keyStrategy = keyStrategy(entity);
Debug.Assert(_changeTrackingStrategy != null, "Change tracking strategy cannot be null.");
Debug.Assert(_keyStrategy != null, "Key strategy cannot be null.");
}
/// <summary>
/// Constructs a wrapper as part of the materialization process. This constructor is only used
/// during materialization where it is known that the entity being wrapped is newly constructed.
/// This means that some checks are not performed that might be needed when thw wrapper is
/// created at other times, and information such as the identity type is passed in because
/// it is readily available in the materializer.
/// </summary>
/// <param name="entity">The entity to wrap</param>
/// <param name="relationshipManager">The RelationshipManager associated with the entity</param>
/// <param name="key">The entity's key</param>
/// <param name="entitySet">The entity set, or null if none is known</param>
/// <param name="context">The context to which the entity should be attached</param>
/// <param name="mergeOption">NoTracking for non-tracked entities, AppendOnly otherwise</param>
/// <param name="identityType">The type of the entity ignoring any possible proxy type</param>
/// <param name="propertyStrategy">A delegate to create the property accesor strategy object</param>
/// <param name="changeTrackingStrategy">A delegate to create the change tracking strategy object</param>
/// <param name="keyStrategy">A delegate to create the entity key strategy object</param>
protected EntityWrapper(TEntity entity, RelationshipManager relationshipManager, EntityKey key, EntitySet set, ObjectContext context, MergeOption mergeOption, Type identityType,
Func<object, IPropertyAccessorStrategy> propertyStrategy, Func<object, IChangeTrackingStrategy> changeTrackingStrategy, Func<object, IEntityKeyStrategy> keyStrategy)
: base(entity, relationshipManager, set, context, mergeOption, identityType)
{
if (relationshipManager == null)
{
throw EntityUtil.UnexpectedNullRelationshipManager();
}
_entity = entity;
_propertyStrategy = propertyStrategy(entity);
_changeTrackingStrategy = changeTrackingStrategy(entity);
_keyStrategy = keyStrategy(entity);
Debug.Assert(_changeTrackingStrategy != null, "Change tracking strategy cannot be null.");
Debug.Assert(_keyStrategy != null, "Key strategy cannot be null.");
_keyStrategy.SetEntityKey(key);
}
// See IEntityWrapper documentation
public override void SetChangeTracker(IEntityChangeTracker changeTracker)
{
_changeTrackingStrategy.SetChangeTracker(changeTracker);
}
// See IEntityWrapper documentation
public override void TakeSnapshot(EntityEntry entry)
{
_changeTrackingStrategy.TakeSnapshot(entry);
}
// See IEntityWrapper documentation
public override EntityKey EntityKey
{
// If no strategy is set, then the key maintained by the wrapper is used,
// otherwise the request is passed to the strategy.
get
{
return _keyStrategy.GetEntityKey();
}
set
{
_keyStrategy.SetEntityKey(value);
}
}
public override EntityKey GetEntityKeyFromEntity()
{
return _keyStrategy.GetEntityKeyFromEntity();
}
public override void CollectionAdd(RelatedEnd relatedEnd, object value)
{
if (_propertyStrategy != null)
{
_propertyStrategy.CollectionAdd(relatedEnd, value);
}
}
public override bool CollectionRemove(RelatedEnd relatedEnd, object value)
{
return _propertyStrategy != null ? _propertyStrategy.CollectionRemove(relatedEnd, value) : false;
}
// See IEntityWrapper documentation
public override void EnsureCollectionNotNull(RelatedEnd relatedEnd)
{
if (_propertyStrategy != null)
{
object collection = _propertyStrategy.GetNavigationPropertyValue(relatedEnd);
if (collection == null)
{
collection = _propertyStrategy.CollectionCreate(relatedEnd);
_propertyStrategy.SetNavigationPropertyValue(relatedEnd, collection);
}
}
}
// See IEntityWrapper documentation
public override object GetNavigationPropertyValue(RelatedEnd relatedEnd)
{
return _propertyStrategy != null ? _propertyStrategy.GetNavigationPropertyValue(relatedEnd) : null;
}
// See IEntityWrapper documentation
public override void SetNavigationPropertyValue(RelatedEnd relatedEnd, object value)
{
if (_propertyStrategy != null)
{
_propertyStrategy.SetNavigationPropertyValue(relatedEnd, value);
}
}
// See IEntityWrapper documentation
public override void RemoveNavigationPropertyValue(RelatedEnd relatedEnd, object value)
{
if (_propertyStrategy != null)
{
object currentValue = _propertyStrategy.GetNavigationPropertyValue(relatedEnd);
if (Object.ReferenceEquals(currentValue, value))
{
_propertyStrategy.SetNavigationPropertyValue(relatedEnd, null);
}
}
}
// See IEntityWrapper documentation
public override object Entity
{
get { return _entity; }
}
// See IEntityWrapper<TEntity> documentation
public override TEntity TypedEntity
{
get { return _entity; }
}
// See IEntityWrapper documentation
public override void SetCurrentValue(EntityEntry entry, StateManagerMemberMetadata member, int ordinal, object target, object value)
{
_changeTrackingStrategy.SetCurrentValue(entry, member, ordinal, target, value);
}
// See IEntityWrapper documentation
public override void UpdateCurrentValueRecord(object value, EntityEntry entry)
{
_changeTrackingStrategy.UpdateCurrentValueRecord(value, entry);
}
}
}
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