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//---------------------------------------------------------------------
// <copyright file="RelationshipManager.cs" company="Microsoft">
// Copyright (c) Microsoft Corporation. All rights reserved.
// </copyright>
//
// @owner Microsoft
// @backupOwner Microsoft
//---------------------------------------------------------------------
namespace System.Data.Objects.DataClasses
{
using System.Collections;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data.Common.Utils;
using System.Data.Mapping;
using System.Data.Metadata.Edm;
using System.Data.Objects.Internal;
using System.Diagnostics;
using System.Linq;
using System.Runtime.Serialization;
/// <summary>
/// Container for the lazily created relationship navigation
/// property objects (collections and refs).
/// </summary>
[Serializable]
public class RelationshipManager
{
// ------------
// Constructors
// ------------
// This method is private in order to force all creation of this
// object to occur through the public static Create method.
// See comments on that method for more details.
private RelationshipManager()
{
}
// ------
// Fields
// ------
// The following fields are serialized. Adding or removing a serialized field is considered
// a breaking change. This includes changing the field type or field name of existing
// serialized fields. If you need to make this kind of change, it may be possible, but it
// will require some custom serialization/deserialization code.
// Note that this field should no longer be used directly. Instead, use the _wrappedOwner
// field. This field is retained only for compatibility with the serialization format introduced in v1.
private IEntityWithRelationships _owner;
private List<RelatedEnd> _relationships;
[NonSerialized]
private bool _nodeVisited;
[NonSerialized]
private IEntityWrapper _wrappedOwner;
// ----------
// Properties
// ----------
/// <summary>
/// Returns a defensive copy of all the known relationships. The copy is defensive because
/// new items may get added to the collection while the caller is iterating over it. Without
/// the copy this would cause an exception for concurrently modifying the collection.
/// </summary>
internal IEnumerable<RelatedEnd> Relationships
{
get
{
EnsureRelationshipsInitialized();
return _relationships.ToArray();
}
}
/// <summary>
/// Lazy initialization of the _relationships collection.
/// </summary>
private void EnsureRelationshipsInitialized()
{
if (null == _relationships)
{
_relationships = new List<RelatedEnd>();
}
}
/// <summary>
/// this flag is used to keep track of nodes which have
/// been visited. Currently used for Exclude operation.
/// </summary>
internal bool NodeVisited
{
get
{
return _nodeVisited;
}
set
{
_nodeVisited = value;
}
}
/// <summary>
/// Provides access to the entity that owns this manager in its wrapped form.
/// </summary>
internal IEntityWrapper WrappedOwner
{
get
{
if (_wrappedOwner == null)
{
_wrappedOwner = EntityWrapperFactory.CreateNewWrapper(_owner, null);
}
return _wrappedOwner;
}
}
// -------
// Methods
// -------
/// <summary>
/// Factory method to create a new RelationshipManager object.
///
/// Used by data classes that support relationships. If the change tracker
/// requests the RelationshipManager property and the data class does not
/// already have a reference to one of these objects, it calls this method
/// to create one, then saves a reference to that object. On subsequent accesses
/// to that property, the data class should return the saved reference.
///
/// The reason for using a factory method instead of a public constructor is to
/// emphasize that this is not something you would normally call outside of a data class.
/// By requiring that these objects are created via this method, developers should
/// give more thought to the operation, and will generally only use it when
/// they explicitly need to get an object of this type. It helps define the intended usage.
/// </summary>
/// <param name="owner">Reference to the entity that is calling this method</param>
/// <exception cref="ArgumentNullException"><paramref name="owner"/> is null</exception>
/// <returns>A new or existing RelationshipManager for the given entity</returns>
public static RelationshipManager Create(IEntityWithRelationships owner)
{
EntityUtil.CheckArgumentNull(owner, "owner");
RelationshipManager rm = new RelationshipManager();
rm._owner = owner;
return rm;
}
/// <summary>
/// Factory method that creates a new, uninitialized RelationshipManager. This should only be
/// used to create a RelationshipManager for an IEntityWrapper for an entity that does not
/// implement IEntityWithRelationships. For entities that implement IEntityWithRelationships,
/// the Create(IEntityWithRelationships) method should be used instead.
/// </summary>
/// <returns>The new RelationshipManager</returns>
internal static RelationshipManager Create()
{
return new RelationshipManager();
}
/// <summary>
/// Replaces the existing wrapped owner with one that potentially contains more information,
/// such as an entity key. Both must wrap the same entity.
/// </summary>
internal void SetWrappedOwner(IEntityWrapper wrappedOwner, object expectedOwner)
{
_wrappedOwner = wrappedOwner;
Debug.Assert(_owner != null || !(wrappedOwner.Entity is IEntityWithRelationships), "_owner should only be null if entity is not IEntityWithRelationships");
// We need to check that the RelationshipManager created by the entity has the correct owner set,
// since the entity can pass any value into RelationshipManager.Create().
if (_owner != null && !Object.ReferenceEquals(expectedOwner, _owner))
{
throw EntityUtil.InvalidRelationshipManagerOwner();
}
if (null != _relationships)
{
// Not using defensive copy here since SetWrappedOwner should not cause change in underlying
// _relationships collection.
foreach (RelatedEnd relatedEnd in _relationships)
{
relatedEnd.SetWrappedOwner(wrappedOwner);
}
}
}
/// <summary>
/// Get the collection of entities related to the current entity using the specified
/// combination of relationship name, source role name, and target role name
/// </summary>
/// <typeparam name="TSourceEntity">Type of the entity in the source role (same as the type of this)</typeparam>
/// <typeparam name="TTargetEntity">Type of the entity in the target role</typeparam>
/// <param name="relationshipName">CSpace-qualified name of the relationship to navigate</param>
/// <param name="sourceRoleName">Name of the source role for the navigation. Indicates the direction of navigation across the relationship.</param>
/// <param name="targetRoleName">Name of the target role for the navigation. Indicates the direction of navigation across the relationship.</param>
/// <param name="sourcePropertyName">Name of the property on the source of the navigation.</param>
/// <param name="targetPropertyName">Name of the property on the target of the navigation.</param>
/// <param name="sourceRoleMultiplicity">Multiplicity of the source role. RelationshipMultiplicity.OneToOne and RelationshipMultiplicity.Zero are both
/// accepted for a reference end, and RelationshipMultiplicity.Many is accepted for a collection</param>
/// <returns>Collection of related entities of type TTargetEntity</returns>
internal EntityCollection<TTargetEntity> GetRelatedCollection<TSourceEntity, TTargetEntity>(string relationshipName,
string sourceRoleName, string targetRoleName, NavigationPropertyAccessor sourceAccessor, NavigationPropertyAccessor targetAccessor,
RelationshipMultiplicity sourceRoleMultiplicity, RelatedEnd existingRelatedEnd)
where TSourceEntity : class
where TTargetEntity : class
{
EntityCollection<TTargetEntity> collection;
RelatedEnd relatedEnd;
TryGetCachedRelatedEnd(relationshipName, targetRoleName, out relatedEnd);
if (existingRelatedEnd == null)
{
if (relatedEnd != null)
{
collection = relatedEnd as EntityCollection<TTargetEntity>;
// Because this is a private method that will only be called for target roles that actually have a
// multiplicity that works with EntityReference, this should never be null. If the user requests
// a collection or reference and it doesn't match the target role multiplicity, it will be detected
// in the public GetRelatedCollection<T> or GetRelatedReference<T>
Debug.Assert(collection != null, "should never receive anything but an EntityCollection here");
return collection;
}
else
{
RelationshipNavigation navigation = new RelationshipNavigation(relationshipName, sourceRoleName, targetRoleName, sourceAccessor, targetAccessor);
return CreateRelatedEnd<TSourceEntity, TTargetEntity>(navigation, sourceRoleMultiplicity, RelationshipMultiplicity.Many, existingRelatedEnd) as EntityCollection<TTargetEntity>;
}
}
else
{
// There is no need to supress events on the existingRelatedEnd because setting events on a disconnected
// EntityCollection is an InvalidOperation
Debug.Assert(existingRelatedEnd._onAssociationChanged == null, "Disconnected RelatedEnd had events");
if (relatedEnd != null)
{
Debug.Assert(_relationships != null, "Expected _relationships to be non-null.");
_relationships.Remove(relatedEnd);
}
RelationshipNavigation navigation = new RelationshipNavigation(relationshipName, sourceRoleName, targetRoleName, sourceAccessor, targetAccessor);
collection = CreateRelatedEnd<TSourceEntity, TTargetEntity>(navigation, sourceRoleMultiplicity, RelationshipMultiplicity.Many, existingRelatedEnd) as EntityCollection<TTargetEntity>;
if (collection != null)
{
bool doCleanup = true;
try
{
RemergeCollections(relatedEnd as EntityCollection<TTargetEntity>, collection);
doCleanup = false;
}
finally
{
// An error occured so we need to put the previous relatedEnd back into the RelationshipManager
if (doCleanup && relatedEnd != null)
{
Debug.Assert(_relationships != null, "Expected _relationships to be non-null.");
_relationships.Remove(collection);
_relationships.Add(relatedEnd);
}
}
}
return collection;
}
}
/// <summary>
/// Re-merge items from collection so that relationship fixup is performed.
/// Ensure that any items in previous collection are excluded from the re-merge
/// </summary>
/// <typeparam name="TTargetEntity"></typeparam>
/// <param name="previousCollection">The previous EntityCollection containing items that have already had fixup performed</param>
/// <param name="collection">The new EntityCollection</param>
private void RemergeCollections<TTargetEntity>(EntityCollection<TTargetEntity> previousCollection,
EntityCollection<TTargetEntity> collection)
where TTargetEntity : class
{
Debug.Assert(collection != null, "collection is null");
// If there is a previousCollection, we only need to merge the items that are
// in the collection but not in the previousCollection
// Ensure that all of the items in the previousCollection are already in the new collection
int relatedEntityCount = 0;
// We will be modifing the collection's enumerator, so we need to make a copy of it
List<IEntityWrapper> tempEntities = new List<IEntityWrapper>(collection.CountInternal);
foreach (IEntityWrapper wrappedEntity in collection.GetWrappedEntities())
{
tempEntities.Add(wrappedEntity);
}
// Iterate through the entities that require merging
// If the previousCollection already contained the entity, no additional work is needed
// If the previousCollection did not contain the entity,
// then remove it from the collection and re-add it to force relationship fixup
foreach (IEntityWrapper wrappedEntity in tempEntities)
{
bool requiresMerge = true;
if (previousCollection != null)
{
// There is no need to merge and do fixup if the entity was already in the previousCollection because
// fixup would have already taken place when it was added to the previousCollection
if (previousCollection.ContainsEntity(wrappedEntity))
{
relatedEntityCount++;
requiresMerge = false;
}
}
if (requiresMerge)
{
// Remove and re-add the item to the collections to force fixup
collection.Remove(wrappedEntity, false);
collection.Add(wrappedEntity);
}
}
// Ensure that all of the items in the previousCollection are already in the new collection
if (previousCollection != null && relatedEntityCount != previousCollection.CountInternal)
{
throw EntityUtil.CannotRemergeCollections();
}
}
/// <summary>
/// Get the entity reference of a related entity using the specified
/// combination of relationship name, source role name, and target role name
/// </summary>
/// <param name="relationshipName">CSpace-qualified name of the relationship to navigate</param>
/// <param name="sourceRoleName">Name of the source role for the navigation. Indicates the direction of navigation across the relationship.</param>
/// <param name="targetRoleName">Name of the target role for the navigation. Indicates the direction of navigation across the relationship.</param>
/// <param name="sourcePropertyName">Name of the property on the source of the navigation.</param>
/// <param name="targetPropertyName">Name of the property on the target of the navigation.</param>
/// <param name="sourceRoleMultiplicity">Multiplicity of the source role. RelationshipMultiplicity.OneToOne and RelationshipMultiplicity.Zero are both
/// accepted for a reference end, and RelationshipMultiplicity.Many is accepted for a collection</param>
/// <returns>Reference for related entity of type TTargetEntity</returns>
internal EntityReference<TTargetEntity> GetRelatedReference<TSourceEntity, TTargetEntity>(string relationshipName,
string sourceRoleName, string targetRoleName, NavigationPropertyAccessor sourceAccessor, NavigationPropertyAccessor targetAccessor,
RelationshipMultiplicity sourceRoleMultiplicity, RelatedEnd existingRelatedEnd)
where TSourceEntity : class
where TTargetEntity : class
{
EntityReference<TTargetEntity> entityRef;
RelatedEnd relatedEnd;
if (TryGetCachedRelatedEnd(relationshipName, targetRoleName, out relatedEnd))
{
entityRef = relatedEnd as EntityReference<TTargetEntity>;
// Because this is a private method that will only be called for target roles that actually have a
// multiplicity that works with EntityReference, this should never be null. If the user requests
// a collection or reference and it doesn't match the target role multiplicity, it will be detected
// in the public GetRelatedCollection<T> or GetRelatedReference<T>
Debug.Assert(entityRef != null, "should never receive anything but an EntityReference here");
return entityRef;
}
else
{
RelationshipNavigation navigation = new RelationshipNavigation(relationshipName, sourceRoleName, targetRoleName, sourceAccessor, targetAccessor);
return CreateRelatedEnd<TSourceEntity, TTargetEntity>(navigation, sourceRoleMultiplicity, RelationshipMultiplicity.One, existingRelatedEnd) as EntityReference<TTargetEntity>;
}
}
/// <summary>
/// Internal version of GetRelatedEnd that works with the o-space navigation property
/// name rather than the c-space relationship name and end name.
/// </summary>
/// <param name="navigationProperty">the name of the property to lookup</param>
/// <returns>the related end for the given property</returns>
internal RelatedEnd GetRelatedEnd(string navigationProperty, bool throwArgumentException = false)
{
IEntityWrapper wrappedOwner = WrappedOwner;
Debug.Assert(wrappedOwner.Entity != null, "Entity is null");
Debug.Assert(wrappedOwner.Context != null, "Context is null");
Debug.Assert(wrappedOwner.Context.MetadataWorkspace != null, "MetadataWorkspace is null");
Debug.Assert(wrappedOwner.Context.Perspective != null, "Perspective is null");
EntityType entityType = wrappedOwner.Context.MetadataWorkspace.GetItem<EntityType>(wrappedOwner.IdentityType.FullName, DataSpace.OSpace);
EdmMember member;
if (!wrappedOwner.Context.Perspective.TryGetMember(entityType, navigationProperty, false, out member) ||
!(member is NavigationProperty))
{
var message = System.Data.Entity.Strings.RelationshipManager_NavigationPropertyNotFound(navigationProperty);
throw throwArgumentException ? (Exception)new ArgumentException(message) : (Exception)new InvalidOperationException(message);
}
NavigationProperty navProp = (NavigationProperty)member;
return GetRelatedEndInternal(navProp.RelationshipType.FullName, navProp.ToEndMember.Name);
}
/// <summary>
/// Returns either an EntityCollection or EntityReference of the correct type for the specified target role in a relationship
/// This is intended to be used in scenarios where the user doesn't have full metadata, including the static type
/// information for both ends of the relationship. This metadata is specified in the EdmRelationshipRoleAttribute
/// on each entity type in the relationship, so the metadata system can retrieve it based on the supplied relationship
/// name and target role name.
/// </summary>
/// <param name="relationshipName">Name of the relationship in which targetRoleName is defined. Can be CSpace-qualified or not.</param>
/// <param name="targetRoleName">Target role to use to retrieve the other end of relationshipName</param>
/// <returns>IRelatedEnd representing the EntityCollection or EntityReference that was retrieved</returns>
public IRelatedEnd GetRelatedEnd(string relationshipName, string targetRoleName)
{
return GetRelatedEndInternal(PrependNamespaceToRelationshipName(relationshipName), targetRoleName);
}
// Internal version of GetRelatedEnd which returns the RelatedEnd as a RelatedEnd rather than an IRelatedEnd
internal RelatedEnd GetRelatedEndInternal(string relationshipName, string targetRoleName)
{
EntityUtil.CheckArgumentNull(relationshipName, "relationshipName");
EntityUtil.CheckArgumentNull(targetRoleName, "targetRoleName");
IEntityWrapper wrappedOwner = WrappedOwner;
if (wrappedOwner.Context == null && wrappedOwner.RequiresRelationshipChangeTracking)
{
throw new InvalidOperationException(System.Data.Entity.Strings.RelationshipManager_CannotGetRelatEndForDetachedPocoEntity);
}
RelatedEnd relatedEnd = null;
// Try to get the AssociationType from metadata. This will contain all of the ospace metadata for this relationship
AssociationType associationType = null;
if (!TryGetRelationshipType(wrappedOwner, wrappedOwner.IdentityType, relationshipName, out associationType))
{
if (_relationships != null)
{
// Look for the RelatedEnd in the list that has already been retrieved
relatedEnd = (from RelatedEnd end in _relationships
where end.RelationshipName == relationshipName &&
end.TargetRoleName == targetRoleName
select end).FirstOrDefault();
}
if (relatedEnd == null && !EntityProxyFactory.TryGetAssociationTypeFromProxyInfo(wrappedOwner, relationshipName, targetRoleName, out associationType))
{
// If the end still cannot be found, throw an exception
throw UnableToGetMetadata(WrappedOwner, relationshipName);
}
}
if (relatedEnd == null)
{
Debug.Assert(associationType != null, "associationType is null");
relatedEnd = GetRelatedEndInternal(relationshipName, targetRoleName, /*existingRelatedEnd*/ null, associationType);
}
return relatedEnd;
}
private RelatedEnd GetRelatedEndInternal(string relationshipName, string targetRoleName, RelatedEnd existingRelatedEnd, AssociationType relationship)
{
return GetRelatedEndInternal(relationshipName, targetRoleName, existingRelatedEnd, relationship, true);
}
private RelatedEnd GetRelatedEndInternal(string relationshipName, string targetRoleName, RelatedEnd existingRelatedEnd, AssociationType relationship, bool throwOnError)
{
Debug.Assert(relationshipName != null, "null relationshipNameFromUser");
Debug.Assert(targetRoleName != null, "null targetRoleName");
// existingRelatedEnd can be null if we are not trying to initialize an existing end
Debug.Assert(relationship != null, "null relationshipType");
AssociationEndMember sourceEnd;
AssociationEndMember targetEnd;
Debug.Assert(relationship.AssociationEndMembers.Count == 2, "Only 2-way relationships are currently supported");
RelatedEnd result = null;
// There can only be two ends because we don't support n-way relationships -- figure out which end is the target and which is the source
// If we want to support n-way relationships in the future, we will need a different overload of GetRelatedEnd that takes the source role name as well
targetEnd = relationship.AssociationEndMembers[1];
if (targetEnd.Identity != targetRoleName)
{
sourceEnd = targetEnd;
targetEnd = relationship.AssociationEndMembers[0];
if (targetEnd.Identity != targetRoleName)
{
if (throwOnError)
{
throw EntityUtil.InvalidTargetRole(relationshipName, targetRoleName, "targetRoleName");
}
else
{
return result;
}
}
}
else
{
sourceEnd = relationship.AssociationEndMembers[0];
}
// Validate that the source type matches the type of the owner
EntityType sourceEntityType = MetadataHelper.GetEntityTypeForEnd(sourceEnd);
Debug.Assert(sourceEntityType.DataSpace == DataSpace.OSpace && sourceEntityType.ClrType != null, "sourceEntityType must contain an ospace type");
Type sourceType = sourceEntityType.ClrType;
IEntityWrapper wrappedOwner = WrappedOwner;
if (!(sourceType.IsAssignableFrom(wrappedOwner.IdentityType)))
{
if (throwOnError)
{
throw EntityUtil.OwnerIsNotSourceType(wrappedOwner.IdentityType.FullName, sourceType.FullName, sourceEnd.Name, relationshipName);
}
}
else if (VerifyRelationship(relationship, sourceEnd.Name, throwOnError))
{
// Call a dynamic method that will call either GetRelatedCollection<T, T> or GetRelatedReference<T, T> for this relationship
result = LightweightCodeGenerator.GetRelatedEnd(this, sourceEnd, targetEnd, existingRelatedEnd);
}
return result;
}
/// <summary>
/// Takes an existing EntityReference that was created with the default constructor and initializes it using the provided relationship and target role names.
/// This method is designed to be used during deserialization only, and will throw an exception if the provided EntityReference has already been initialized,
/// if the relationship manager already contains a relationship with this name and target role, or if the relationship manager is already attached to a ObjectContext.
/// </summary>
/// <typeparam name="TTargetEntity">Type of the entity represented by targetRoleName</typeparam>
/// <param name="relationshipName"></param>
/// <param name="targetRoleName"></param>
/// <param name="entityReference"></param>
[Browsable(false)]
[EditorBrowsable(EditorBrowsableState.Never)]
public void InitializeRelatedReference<TTargetEntity>(string relationshipName, string targetRoleName, EntityReference<TTargetEntity> entityReference)
where TTargetEntity : class
{
EntityUtil.CheckArgumentNull(relationshipName, "relationshipName");
EntityUtil.CheckArgumentNull(targetRoleName, "targetRoleName");
EntityUtil.CheckArgumentNull(entityReference, "entityReference");
if (entityReference.WrappedOwner.Entity != null)
{
throw EntityUtil.ReferenceAlreadyInitialized();
}
IEntityWrapper wrappedOwner = WrappedOwner;
if (wrappedOwner.Context != null && wrappedOwner.MergeOption != MergeOption.NoTracking)
{
throw EntityUtil.RelationshipManagerAttached();
}
// We need the CSpace-qualified name in order to determine if this relationship already exists, so look it up.
// If the relationship doesn't exist, we will use this type information to determine how to initialize the reference
relationshipName = PrependNamespaceToRelationshipName(relationshipName);
AssociationType relationship = GetRelationshipType(wrappedOwner.IdentityType, relationshipName);
RelatedEnd relatedEnd;
if (TryGetCachedRelatedEnd(relationshipName, targetRoleName, out relatedEnd))
{
// For some serialization scenarios, we have to allow replacing a related end that we already know about, but in those scenarios
// the end is always empty, so we can further restrict the user calling method method directly by doing this extra validation
if (!relatedEnd.IsEmpty())
{
entityReference.InitializeWithValue(relatedEnd);
}
Debug.Assert(_relationships != null, "Expected _relationships to be non-null.");
_relationships.Remove(relatedEnd);
}
EntityReference<TTargetEntity> reference = GetRelatedEndInternal(relationshipName, targetRoleName, entityReference, relationship) as EntityReference<TTargetEntity>;
if (reference == null)
{
throw EntityUtil.ExpectedReferenceGotCollection(typeof(TTargetEntity).Name, targetRoleName, relationshipName);
}
}
/// <summary>
/// Takes an existing EntityCollection that was created with the default constructor and initializes it using the provided relationship and target role names.
/// This method is designed to be used during deserialization only, and will throw an exception if the provided EntityCollection has already been initialized,
/// or if the relationship manager is already attached to a ObjectContext.
/// </summary>
/// <typeparam name="TTargetEntity">Type of the entity represented by targetRoleName</typeparam>
/// <param name="relationshipName"></param>
/// <param name="targetRoleName"></param>
/// <param name="entityCollection"></param>
[Browsable(false)]
[EditorBrowsable(EditorBrowsableState.Never)]
public void InitializeRelatedCollection<TTargetEntity>(string relationshipName, string targetRoleName, EntityCollection<TTargetEntity> entityCollection)
where TTargetEntity : class
{
EntityUtil.CheckArgumentNull(relationshipName, "relationshipName");
EntityUtil.CheckArgumentNull(targetRoleName, "targetRoleName");
EntityUtil.CheckArgumentNull(entityCollection, "entityCollection");
if (entityCollection.WrappedOwner.Entity != null)
{
throw EntityUtil.CollectionAlreadyInitialized();
}
IEntityWrapper wrappedOwner = WrappedOwner;
if (wrappedOwner.Context != null && wrappedOwner.MergeOption != MergeOption.NoTracking)
{
throw EntityUtil.CollectionRelationshipManagerAttached();
}
// We need the CSpace-qualified name in order to determine if this relationship already exists, so look it up.
// If the relationship doesn't exist, we will use this type information to determine how to initialize the reference
relationshipName = PrependNamespaceToRelationshipName(relationshipName);
AssociationType relationship = GetRelationshipType(wrappedOwner.IdentityType, relationshipName);
EntityCollection<TTargetEntity> collection = GetRelatedEndInternal(relationshipName, targetRoleName, entityCollection, relationship) as EntityCollection<TTargetEntity>;
if (collection == null)
{
throw EntityUtil.ExpectedCollectionGotReference(typeof(TTargetEntity).Name, targetRoleName, relationshipName);
}
}
/// <summary>
/// Given a relationship name that may or may not be qualified with a namespace name, this method
/// attempts to lookup a namespace using the entity type that owns this RelationshipManager as a
/// source and adds that namespace to the front of the relationship name. If the namespace
/// can't be found, then the relationshipName is returned untouched and the expectation is that
/// other validations will fail later in the code paths that use this.
/// This method should only be used at the imediate top-level public surface since all internal
/// calls are expected to use fully qualified names already.
/// </summary>
private string PrependNamespaceToRelationshipName(string relationshipName)
{
EntityUtil.CheckArgumentNull(relationshipName, "relationshipName");
if (!relationshipName.Contains('.'))
{
string identityName = WrappedOwner.IdentityType.FullName;
ObjectItemCollection objectItemCollection = GetObjectItemCollection(WrappedOwner);
EdmType entityType = null;
if (objectItemCollection != null)
{
objectItemCollection.TryGetItem<EdmType>(identityName, out entityType);
}
else
{
Dictionary<string, EdmType> types = ObjectItemCollection.LoadTypesExpensiveWay(WrappedOwner.IdentityType.Assembly);
if (types != null)
{
types.TryGetValue(identityName, out entityType);
}
}
ClrEntityType clrEntityType = entityType as ClrEntityType;
if (clrEntityType != null)
{
string ns = clrEntityType.CSpaceNamespaceName;
Debug.Assert(!string.IsNullOrEmpty(ns), "Expected non-empty namespace for type.");
return ns + "." + relationshipName;
}
}
return relationshipName;
}
/// <summary>
/// Trys to get an ObjectItemCollection and returns null if it can;t be found.
/// </summary>
private static ObjectItemCollection GetObjectItemCollection(IEntityWrapper wrappedOwner)
{
if (wrappedOwner.Context != null && wrappedOwner.Context.MetadataWorkspace != null)
{
return (ObjectItemCollection)wrappedOwner.Context.MetadataWorkspace.GetItemCollection(DataSpace.OSpace);
}
return null;
}
/// <summary>
/// Trys to get the EntityType metadata and returns false if it can't be found.
/// </summary>
private bool TryGetOwnerEntityType(out EntityType entityType)
{
DefaultObjectMappingItemCollection mappings;
Map map;
if (TryGetObjectMappingItemCollection(WrappedOwner, out mappings) &&
mappings.TryGetMap(WrappedOwner.IdentityType.FullName, DataSpace.OSpace, out map))
{
ObjectTypeMapping objectMap = (ObjectTypeMapping)map;
if (Helper.IsEntityType(objectMap.EdmType))
{
entityType = (EntityType)objectMap.EdmType;
return true;
}
}
entityType = null;
return false;
}
/// <summary>
/// Trys to get an DefaultObjectMappingItemCollection and returns false if it can't be found.
/// </summary>
private static bool TryGetObjectMappingItemCollection(IEntityWrapper wrappedOwner, out DefaultObjectMappingItemCollection collection)
{
if (wrappedOwner.Context != null && wrappedOwner.Context.MetadataWorkspace != null)
{
collection = (DefaultObjectMappingItemCollection)wrappedOwner.Context.MetadataWorkspace.GetItemCollection(DataSpace.OCSpace);
return collection != null;
}
collection = null;
return false;
}
internal static bool TryGetRelationshipType(IEntityWrapper wrappedOwner, Type entityClrType, string relationshipName, out AssociationType associationType)
{
ObjectItemCollection objectItemCollection = GetObjectItemCollection(wrappedOwner);
if (objectItemCollection != null)
{
associationType = objectItemCollection.GetRelationshipType(entityClrType, relationshipName);
}
else
{
associationType = ObjectItemCollection.GetRelationshipTypeExpensiveWay(entityClrType, relationshipName);
}
return (associationType != null);
}
private AssociationType GetRelationshipType(Type entityClrType, string relationshipName)
{
AssociationType associationType = null;
if (!TryGetRelationshipType(WrappedOwner, entityClrType, relationshipName, out associationType))
{
throw UnableToGetMetadata(WrappedOwner, relationshipName);
}
return associationType;
}
internal static Exception UnableToGetMetadata(IEntityWrapper wrappedOwner, string relationshipName)
{
ArgumentException argException = EntityUtil.UnableToFindRelationshipTypeInMetadata(relationshipName, "relationshipName");
if (EntityProxyFactory.IsProxyType(wrappedOwner.Entity.GetType()))
{
return EntityUtil.ProxyMetadataIsUnavailable(wrappedOwner.IdentityType, argException);
}
else
{
return argException;
}
}
private IEnumerable<AssociationEndMember> GetAllTargetEnds(EntityType ownerEntityType, EntitySet ownerEntitySet)
{
foreach (AssociationSet assocSet in MetadataHelper.GetAssociationsForEntitySet(ownerEntitySet))
{
EntityType end2EntityType = ((AssociationType)assocSet.ElementType).AssociationEndMembers[1].GetEntityType();
if (end2EntityType.IsAssignableFrom(ownerEntityType))
{
yield return ((AssociationType)assocSet.ElementType).AssociationEndMembers[0];
}
// not "else" because of associations between the same entity sets
EntityType end1EntityType = ((AssociationType)assocSet.ElementType).AssociationEndMembers[0].GetEntityType();
if (end1EntityType.IsAssignableFrom(ownerEntityType))
{
yield return ((AssociationType)assocSet.ElementType).AssociationEndMembers[1];
}
}
}
/// <summary>
/// Retrieves the AssociationEndMembers that corespond to the target end of a relationship
/// given a specific CLR type that exists on the source end of a relationship
/// Note: this method can be very expensive if this RelationshipManager is not attached to an
/// ObjectContext because no OSpace Metadata is available
/// </summary>
/// <param name="entityClrType">A CLR type that is on the source role of the relationship</param>
/// <returns>The OSpace EntityType that represents this CLR type</returns>
private IEnumerable<AssociationEndMember> GetAllTargetEnds(Type entityClrType)
{
ObjectItemCollection objectItemCollection = GetObjectItemCollection(WrappedOwner);
IEnumerable<AssociationType> associations = null;
if (objectItemCollection != null)
{
// Metadata is available
associations = objectItemCollection.GetItems<AssociationType>();
}
else
{
// No metadata is available, attempt to load the metadata on the fly to retrieve the AssociationTypes
associations = ObjectItemCollection.GetAllRelationshipTypesExpensiveWay(entityClrType.Assembly);
}
foreach (AssociationType association in associations)
{
// Check both ends for the presence of the source CLR type
RefType referenceType = association.AssociationEndMembers[0].TypeUsage.EdmType as RefType;
if (referenceType != null && referenceType.ElementType.ClrType.IsAssignableFrom(entityClrType))
{
// Return the target end
yield return association.AssociationEndMembers[1];
}
referenceType = association.AssociationEndMembers[1].TypeUsage.EdmType as RefType;
if (referenceType != null && referenceType.ElementType.ClrType.IsAssignableFrom(entityClrType))
{
// Return the target end
yield return association.AssociationEndMembers[0];
}
}
yield break;
}
private bool VerifyRelationship(AssociationType relationship, string sourceEndName, bool throwOnError)
{
IEntityWrapper wrappedOwner = WrappedOwner;
if (wrappedOwner.Context == null)
{
return true;// if not added to cache, can not decide- for now
}
EntityKey ownerKey = null;
ownerKey = wrappedOwner.EntityKey;
if (null == (object)ownerKey)
{
return true; // if not added to cache, can not decide- for now
}
TypeUsage associationTypeUsage;
AssociationSet association = null;
bool isVerified = true;
// First, get the CSpace association type from the relationship name, since the helper method looks up
// association set in the CSpace, since there is no Entity Container in the OSpace
if (wrappedOwner.Context.Perspective.TryGetTypeByName(relationship.FullName, false/*ignoreCase*/, out associationTypeUsage))
{
//Get the entity container first
EntityContainer entityContainer = wrappedOwner.Context.MetadataWorkspace.GetEntityContainer(
ownerKey.EntityContainerName, DataSpace.CSpace);
EntitySet entitySet;
// Get the association set from the entity container, given the association type it refers to, and the entity set
// name that the source end refers to
association = MetadataHelper.GetAssociationsForEntitySetAndAssociationType(entityContainer, ownerKey.EntitySetName,
(AssociationType)associationTypeUsage.EdmType, sourceEndName, out entitySet);
if (association == null)
{
if (throwOnError)
{
throw EntityUtil.NoRelationshipSetMatched(relationship.FullName);
}
else
{
isVerified = false;
}
}
else
{
Debug.Assert(association.AssociationSetEnds[sourceEndName].EntitySet == entitySet, "AssociationSetEnd does have the matching EntitySet");
}
}
return isVerified;
}
/// <summary>
/// Get the collection of a related entity using the specified
/// combination of relationship name, and target role name.
/// Only supports 2-way relationships.
/// </summary>
/// <param name="relationshipName">Name of the relationship in which targetRoleName is defined. Can be CSpace-qualified or not.</param>
/// <param name="targetRoleName">Name of the target role for the navigation. Indicates the direction of navigation across the relationship.</param>
/// <returns>Collection of entities of type TTargetEntity</returns>
public EntityCollection<TTargetEntity> GetRelatedCollection<TTargetEntity>(string relationshipName, string targetRoleName)
where TTargetEntity : class
{
EntityCollection<TTargetEntity> collection = GetRelatedEndInternal(PrependNamespaceToRelationshipName(relationshipName), targetRoleName) as EntityCollection<TTargetEntity>;
if (collection == null)
{
throw EntityUtil.ExpectedCollectionGotReference(typeof(TTargetEntity).Name, targetRoleName, relationshipName);
}
return collection;
}
/// <summary>
/// Get the entity reference of a related entity using the specified
/// combination of relationship name, and target role name.
/// Only supports 2-way relationships.
/// </summary>
/// <param name="relationshipName">Name of the relationship in which targetRoleName is defined. Can be CSpace-qualified or not.</param>
/// <param name="targetRoleName">Name of the target role for the navigation. Indicates the direction of navigation across the relationship.</param>
/// <returns>Reference for related entity of type TTargetEntity</returns>
public EntityReference<TTargetEntity> GetRelatedReference<TTargetEntity>(string relationshipName, string targetRoleName)
where TTargetEntity : class
{
EntityReference<TTargetEntity> reference = GetRelatedEndInternal(PrependNamespaceToRelationshipName(relationshipName), targetRoleName) as EntityReference<TTargetEntity>;
if (reference == null)
{
throw EntityUtil.ExpectedReferenceGotCollection(typeof(TTargetEntity).Name, targetRoleName, relationshipName);
}
return reference;
}
/// <summary>
/// Gets collection or ref of related entity for a particular navigation.
/// </summary>
/// <param name="navigation">
/// Describes the relationship and navigation direction
/// </param>
/// <param name="relationshipFixer">
/// Encapsulates information about the other end's type and cardinality,
/// and knows how to create the other end
/// </param>
/// <returns></returns>
internal RelatedEnd GetRelatedEnd(RelationshipNavigation navigation, IRelationshipFixer relationshipFixer)
{
RelatedEnd relatedEnd;
if (TryGetCachedRelatedEnd(navigation.RelationshipName, navigation.To, out relatedEnd))
{
return relatedEnd;
}
else
{
relatedEnd = relationshipFixer.CreateSourceEnd(navigation, this);
Debug.Assert(null != relatedEnd, "CreateSourceEnd should always return a valid RelatedEnd");
return relatedEnd;
}
}
/// <summary>
/// Factory method for creating new related ends
/// </summary>
/// <typeparam name="TSourceEntity">Type of the source end</typeparam>
/// <typeparam name="TTargetEntity">Type of the target end</typeparam>
/// <param name="navigation">RelationshipNavigation to be set on the new RelatedEnd</param>
/// <param name="sourceRoleMultiplicity">Multiplicity of the source role</param>
/// <param name="targetRoleMultiplicity">Multiplicity of the target role</param>
/// <param name="existingRelatedEnd">An existing related end to initialize instead of creating a new one</param>
/// <returns>new EntityCollection or EntityReference, depending on the specified target multiplicity</returns>
internal RelatedEnd CreateRelatedEnd<TSourceEntity, TTargetEntity>(RelationshipNavigation navigation, RelationshipMultiplicity sourceRoleMultiplicity, RelationshipMultiplicity targetRoleMultiplicity, RelatedEnd existingRelatedEnd)
where TSourceEntity : class
where TTargetEntity : class
{
IRelationshipFixer relationshipFixer = new RelationshipFixer<TSourceEntity, TTargetEntity>(sourceRoleMultiplicity, targetRoleMultiplicity);
RelatedEnd relatedEnd = null;
IEntityWrapper wrappedOwner = WrappedOwner;
switch (targetRoleMultiplicity)
{
case RelationshipMultiplicity.ZeroOrOne:
case RelationshipMultiplicity.One:
if (existingRelatedEnd != null)
{
Debug.Assert(wrappedOwner.Context == null || wrappedOwner.MergeOption == MergeOption.NoTracking, "Expected null context when initializing an existing related end");
existingRelatedEnd.InitializeRelatedEnd(wrappedOwner, navigation, relationshipFixer);
relatedEnd = existingRelatedEnd;
}
else
{
relatedEnd = new EntityReference<TTargetEntity>(wrappedOwner, navigation, relationshipFixer);
}
break;
case RelationshipMultiplicity.Many:
if (existingRelatedEnd != null)
{
Debug.Assert(wrappedOwner.Context == null || wrappedOwner.MergeOption == MergeOption.NoTracking, "Expected null context or NoTracking when initializing an existing related end");
existingRelatedEnd.InitializeRelatedEnd(wrappedOwner, navigation, relationshipFixer);
relatedEnd = existingRelatedEnd;
}
else
{
relatedEnd = new EntityCollection<TTargetEntity>(wrappedOwner, navigation, relationshipFixer);
}
break;
default:
throw EntityUtil.InvalidEnumerationValue(typeof(RelationshipMultiplicity), (int)targetRoleMultiplicity);
}
// Verify that we can attach the context successfully before adding to our list of relationships
if (wrappedOwner.Context != null)
{
relatedEnd.AttachContext(wrappedOwner.Context, wrappedOwner.MergeOption);
}
EnsureRelationshipsInitialized();
_relationships.Add(relatedEnd);
return relatedEnd;
}
/// <summary>
/// Returns an enumeration of all the related ends. The enumeration
/// will be empty if the relationships have not been populated.
/// </summary>
public IEnumerable<IRelatedEnd> GetAllRelatedEnds()
{
IEntityWrapper wrappedOwner = WrappedOwner;
EntityType entityType;
if (wrappedOwner.Context != null && wrappedOwner.Context.MetadataWorkspace != null && TryGetOwnerEntityType(out entityType))
{
// For attached scenario:
// MEST: This returns RelatedEnds representing AssociationTypes which belongs to AssociationSets
// which have one end of EntitySet of wrappedOwner.Entity's EntitySet
Debug.Assert(wrappedOwner.EntityKey != null, "null entityKey on a attached entity");
EntitySet entitySet = wrappedOwner.Context.GetEntitySet(wrappedOwner.EntityKey.EntitySetName, wrappedOwner.EntityKey.EntityContainerName);
foreach (AssociationEndMember endMember in GetAllTargetEnds(entityType, entitySet))
{
yield return GetRelatedEnd(endMember.DeclaringType.FullName, endMember.Name);
}
}
else
{
// Disconnected scenario
// MEST: this returns RelatedEnds representing all AssociationTypes which have one end of type of wrappedOwner.Entity's type.
// The returned collection of RelatedEnds is a superset of RelatedEnds which can make sense for a single entity, because
// an entity can belong only to one EntitySet. Note that the ideal would be to return the same collection as for attached scenario,
// but it's not possible because we don't know to which EntitySet the wrappedOwner.Entity belongs.
if (wrappedOwner.Entity != null)
{
foreach (AssociationEndMember endMember in GetAllTargetEnds(wrappedOwner.IdentityType))
{
yield return GetRelatedEnd(endMember.DeclaringType.FullName, endMember.Name);
}
}
}
yield break;
}
[EditorBrowsable(EditorBrowsableState.Never)]
[Browsable(false)]
[OnSerializingAttribute]
public void OnSerializing(StreamingContext context)
{
IEntityWrapper wrappedOwner = WrappedOwner;
if (!(wrappedOwner.Entity is IEntityWithRelationships))
{
throw new InvalidOperationException(System.Data.Entity.Strings.RelatedEnd_CannotSerialize("RelationshipManager"));
}
// If we are attached to a context we need to go fixup the detached entity key on any EntityReferences
if (wrappedOwner.Context != null && wrappedOwner.MergeOption != MergeOption.NoTracking)
{
foreach (RelatedEnd relatedEnd in GetAllRelatedEnds())
{
EntityReference reference = relatedEnd as EntityReference;
if (reference != null && reference.EntityKey != null)
{
reference.DetachedEntityKey = reference.EntityKey;
}
}
}
}
// ----------------
// Internal Methods
// ----------------
internal bool HasRelationships
{
get { return _relationships != null; }
}
/// <summary>
/// Add the rest of the graph, attached to this owner, to ObjectStateManager
/// </summary>
/// <param name="doAttach">if TRUE, the rest of the graph is attached directly as Unchanged
/// without calling AcceptChanges()</param>
internal void AddRelatedEntitiesToObjectStateManager(bool doAttach)
{
if (null != _relationships)
{
bool doCleanup = true;
try
{
// Create a copy of this list because with self references, the set of relationships can change
foreach (RelatedEnd relatedEnd in Relationships)
{
relatedEnd.Include(/*addRelationshipAsUnchanged*/false, doAttach);
}
doCleanup = false;
}
finally
{
// If error happens, while attaching entity graph to context, clean-up
// is done on the Owner entity and all its relating entities.
if (doCleanup)
{
IEntityWrapper wrappedOwner = WrappedOwner;
Debug.Assert(wrappedOwner.Context != null && wrappedOwner.Context.ObjectStateManager != null, "Null context or ObjectStateManager");
TransactionManager transManager = wrappedOwner.Context.ObjectStateManager.TransactionManager;
// The graph being attached is connected to graph already existing in the OSM only through "promoted" relationships
// (relationships which originally existed only in OSM between key entries and entity entries but later were
// "promoted" to normal relationships in EntityRef/Collection when the key entries were promoted).
// The cleanup code traverse all the graph being added to the OSM, so we have to disconnect it from the graph already
// existing in the OSM by degrading promoted relationships.
wrappedOwner.Context.ObjectStateManager.DegradePromotedRelationships();
NodeVisited = true;
RemoveRelatedEntitiesFromObjectStateManager(wrappedOwner);
EntityEntry entry;
Debug.Assert(doAttach == (transManager.IsAttachTracking), "In attach the recovery collection should be not null");
if (transManager.IsAttachTracking &&
transManager.PromotedKeyEntries.TryGetValue(wrappedOwner.Entity, out entry))
{
// This is executed only in the cleanup code from ObjectContext.AttachTo()
// If the entry was promoted in AttachTo(), it has to be degraded now instead of being deleted.
entry.DegradeEntry();
}
else
{
RelatedEnd.RemoveEntityFromObjectStateManager(wrappedOwner);
}
}
}
}
}
// Method is used to remove all entities and relationships, of a given entity
// graph, from ObjectStateManager. This method is used when adding entity graph,
// or a portion of it, raise exception.
internal static void RemoveRelatedEntitiesFromObjectStateManager(IEntityWrapper wrappedEntity)
{
Debug.Assert(wrappedEntity != null, "IEntityWrapper instance is null.");
foreach (RelatedEnd relatedEnd in wrappedEntity.RelationshipManager.Relationships)
{
// only some of the related ends may have gotten attached, so just skip the ones that weren't
if (relatedEnd.ObjectContext != null)
{
Debug.Assert(!relatedEnd.UsingNoTracking, "Shouldn't be touching the state manager with entities that were retrieved with NoTracking");
relatedEnd.Exclude();
relatedEnd.DetachContext();
}
}
}
// Remove entity from its relationships and do cascade delete if required.
// All removed relationships are marked for deletion and all cascade deleted
// entitites are also marked for deletion.
internal void RemoveEntityFromRelationships()
{
if (null != _relationships)
{
foreach (RelatedEnd relatedEnd in Relationships)
{
relatedEnd.RemoveAll();
}
}
}
/// <summary>
/// Traverse the relationships and find all the dependent ends that contain FKs, then attempt
/// to null all of those FKs.
/// </summary>
internal void NullAllFKsInDependentsForWhichThisIsThePrincipal()
{
if (_relationships != null)
{
// Build a list of the dependent RelatedEnds because with overlapping FKs we could
// end up removing a relationship before we have suceeded in nulling all the FK values
// for that relationship.
var dependentEndsToProcess = new List<EntityReference>();
foreach (RelatedEnd relatedEnd in Relationships)
{
if (relatedEnd.IsForeignKey)
{
foreach (IEntityWrapper dependent in relatedEnd.GetWrappedEntities())
{
var dependentEnd = relatedEnd.GetOtherEndOfRelationship(dependent);
if (dependentEnd.IsDependentEndOfReferentialConstraint(checkIdentifying: false))
{
Debug.Assert(dependentEnd is EntityReference, "Dependent end in FK relationship should always be a reference.");
dependentEndsToProcess.Add((EntityReference)dependentEnd);
}
}
}
}
foreach (EntityReference dependentEnd in dependentEndsToProcess)
{
dependentEnd.NullAllForeignKeys();
}
}
}
// Removes entity from its relationships.
// Relationship entries are removed from ObjectStateManager if owner is in Added state
// or when owner is "many" end of the relationship
internal void DetachEntityFromRelationships(EntityState ownerEntityState)
{
if (null != _relationships)
{
foreach (RelatedEnd relatedEnd in Relationships)
{
relatedEnd.DetachAll(ownerEntityState);
}
}
}
//For a given relationship removes passed in entity from owners relationship
internal void RemoveEntity(string toRole, string relationshipName, IEntityWrapper wrappedEntity)
{
Debug.Assert(wrappedEntity != null, "IEntityWrapper instance is null.");
RelatedEnd relatedEnd;
if (TryGetCachedRelatedEnd(relationshipName, toRole, out relatedEnd))
{
relatedEnd.Remove(wrappedEntity, false);
}
}
internal void ClearRelatedEndWrappers()
{
if (_relationships != null)
{
foreach (IRelatedEnd relatedEnd in Relationships)
{
((RelatedEnd)relatedEnd).ClearWrappedValues();
}
}
}
// Method used to retrieve properties from principal entities.
// Parameter includeOwnValues means that values from current entity should be also added to "properties"
// includeOwnValues is false only when this method is called from ObjectStateEntry.AcceptChanges()
// Parmeter "visited" is a set containig entities which were already visited during traversing the graph.
// If _owner already exists in the set, it means that there is a cycle in the graph of relationships with RI Constraints.
internal void RetrieveReferentialConstraintProperties(out Dictionary<string, KeyValuePair<object, IntBox>> properties, HashSet<object> visited, bool includeOwnValues)
{
IEntityWrapper wrappedOwner = WrappedOwner;
Debug.Assert(wrappedOwner.Entity != null);
Debug.Assert(visited != null);
// Dictionary< propertyName, <propertyValue, counter>>
properties = new Dictionary<string, KeyValuePair<object, IntBox>>();
EntityKey ownerKey = wrappedOwner.EntityKey;
Debug.Assert((object)ownerKey != null);
// If the key is temporary, get values of referential constraint properties from principal entities
if (ownerKey.IsTemporary)
{
// Find property names which should be retrieved
List<string> propertiesToRetrieve;
bool propertiesToPropagateExist; // not used
this.FindNamesOfReferentialConstraintProperties(out propertiesToRetrieve, out propertiesToPropagateExist, skipFK: false);
if (propertiesToRetrieve != null)
{
// At first try to retrieve properties from entities which are in collections or references.
// This is the most common scenario.
// Only if properties couldn't be retrieved this way, try to retrieve properties from related stubs.
if (_relationships != null)
{
// Not using defensive copy here since RetrieveReferentialConstraintProperties should not cause change in underlying
// _relationships collection.
foreach (RelatedEnd relatedEnd in _relationships)
{
// NOTE: If the following call throws UnableToRetrieveReferentialConstraintProperties,
// it means that properties couldn't be found in indirectly related entities,
// so it doesn't make sense to search for properties in directly related stubs,
// so exception is not being caught here.
relatedEnd.RetrieveReferentialConstraintProperties(properties, visited);
}
}
// Check if all properties were retrieved.
// There are 3 scenarios in which not every expected property can be retrieved:
// 1. There is no related entity from which the property is supposed to be retrieved.
// 2. Related entity which supposed to contains the property doesn't have fixed entity key.
// 3. Property should be retrieved from related key entry
if (!CheckIfAllPropertiesWereRetrieved(properties, propertiesToRetrieve))
{
// Properties couldn't be found in entities in collections or refrences.
// Try to find missing properties in related key entries.
// This process is slow but it is not a common case.
EntityEntry entry = wrappedOwner.Context.ObjectStateManager.FindEntityEntry(ownerKey);
Debug.Assert(entry != null, "Owner entry not found in the object state manager");
entry.RetrieveReferentialConstraintPropertiesFromKeyEntries(properties);
// Check again if all properties were retrieved.
if (!CheckIfAllPropertiesWereRetrieved(properties, propertiesToRetrieve))
{
throw EntityUtil.UnableToRetrieveReferentialConstraintProperties();
}
}
}
}
// 1. If key is temporary, properties from principal entities were retrieved above.
// The other key properties are properties which are not Dependent end of some Referential Constraint.
// 2. If key is not temporary and this method was not called from AcceptChanges() - all key values
// of the current entity are added to 'properties'.
if (!ownerKey.IsTemporary || includeOwnValues)
{
// NOTE this part is never executed when the method is called from ObjectStateManager.AcceptChanges(),
// so we don't try to "retrieve" properties from the the same (callers) entity.
EntityEntry entry = wrappedOwner.Context.ObjectStateManager.FindEntityEntry(ownerKey);
Debug.Assert(entry != null, "Owner entry not found in the object state manager");
entry.GetOtherKeyProperties(properties);
}
}
// properties dictionary contains name of property, its value and coutner saying how many times this property was retrieved from principal entities
private static bool CheckIfAllPropertiesWereRetrieved(Dictionary<string, KeyValuePair<object, IntBox>> properties, List<string> propertiesToRetrieve)
{
Debug.Assert(properties != null);
Debug.Assert(propertiesToRetrieve != null);
bool isSuccess = true;
List<int> countersCopy = new List<int>();
ICollection<KeyValuePair<object, IntBox>> values = properties.Values;
// Create copy of counters (needed in case of failure)
foreach (KeyValuePair<object, IntBox> valueCounterPair in values)
{
countersCopy.Add(valueCounterPair.Value.Value);
}
foreach (string name in propertiesToRetrieve)
{
if (!properties.ContainsKey(name))
{
isSuccess = false;
break;
}
KeyValuePair<object, IntBox> valueCounterPair = properties[name];
valueCounterPair.Value.Value = valueCounterPair.Value.Value - 1;
if (valueCounterPair.Value.Value < 0)
{
isSuccess = false;
break;
}
}
// Check if all the coutners equal 0
if (isSuccess)
{
foreach (KeyValuePair<object, IntBox> valueCounterPair in values)
{
if (valueCounterPair.Value.Value != 0)
{
isSuccess = false;
break;
}
}
}
// Restore counters in case of failure
if (!isSuccess)
{
IEnumerator<int> enumerator = countersCopy.GetEnumerator();
foreach (KeyValuePair<object, IntBox> valueCounterPair in values)
{
enumerator.MoveNext();
valueCounterPair.Value.Value = enumerator.Current;
}
}
return isSuccess;
}
// Check consistency between properties of current entity and Principal entities
// If some of Principal entities don't exist or some property cannot be checked - this is violation of RI Constraints
internal void CheckReferentialConstraintProperties(EntityEntry ownerEntry)
{
Debug.Assert(ownerEntry != null);
List<string> propertiesToRetrieve; // used to check if the owner is a dependent end of some RI Constraint
bool propertiesToPropagateExist; // used to check if the owner is a principal end of some RI Constraint
this.FindNamesOfReferentialConstraintProperties(out propertiesToRetrieve, out propertiesToPropagateExist, skipFK: false);
if ((propertiesToRetrieve != null || propertiesToPropagateExist) &&
_relationships != null)
{
// Not using defensive copy here since CheckReferentialConstraintProperties should not cause change in underlying
// _relationships collection.
foreach (RelatedEnd relatedEnd in _relationships)
{
if (!relatedEnd.CheckReferentialConstraintProperties(ownerEntry))
{
throw EntityUtil.InconsistentReferentialConstraintProperties();
}
}
}
}
// ----------------
// Private Methods
// ----------------
// This method is required to maintain compatibility with the v1 binary serialization format.
// In particular, it recreates a entity wrapper from the serialized owner.
// Note that this is only expected to work for non-POCO entities, since serialization of POCO
// entities will not result in serialization of the RelationshipManager or its related objects.
[EditorBrowsable(EditorBrowsableState.Never)]
[Browsable(false)]
[OnDeserialized()]
public void OnDeserialized(StreamingContext context)
{
// Note that when deserializing, the context is always null since we never serialize
// the context with the entity.
_wrappedOwner = EntityWrapperFactory.WrapEntityUsingContext(_owner, null);
}
/// <summary>
/// Searches the list of relationships for an entry with the specified relationship name and role names
/// </summary>
/// <param name="relationshipName">CSpace-qualified name of the relationship</param>
/// <param name="targetRoleName">name of the target role</param>
/// <param name="relatedEnd">the RelatedEnd if found, otherwise null</param>
/// <returns>true if the entry found, false otherwise</returns>
private bool TryGetCachedRelatedEnd(string relationshipName, string targetRoleName, out RelatedEnd relatedEnd)
{
relatedEnd = null;
if (null != _relationships)
{
// Not using defensive copy here since loop should not cause change in underlying
// _relationships collection.
foreach (RelatedEnd end in _relationships)
{
RelationshipNavigation relNav = end.RelationshipNavigation;
if (relNav.RelationshipName == relationshipName && relNav.To == targetRoleName)
{
relatedEnd = end;
return true;
}
}
}
return false;
}
// Find properties which are Dependent/Principal ends of some referential constraint
// Returned lists are never null.
// NOTE This method will be removed when bug 505935 is solved
// Returns true if any FK relationships were skipped so that they can be checked again after fixup
internal bool FindNamesOfReferentialConstraintProperties(out List<string> propertiesToRetrieve, out bool propertiesToPropagateExist, bool skipFK)
{
IEntityWrapper wrappedOwner = WrappedOwner;
Debug.Assert(wrappedOwner.Entity != null);
EntityKey ownerKey = wrappedOwner.EntityKey;
EntityUtil.CheckEntityKeyNull(ownerKey);
propertiesToRetrieve = null;
propertiesToPropagateExist = false;
EntityUtil.CheckContextNull(wrappedOwner.Context);
EntitySet entitySet = ownerKey.GetEntitySet(wrappedOwner.Context.MetadataWorkspace);
Debug.Assert(entitySet != null, "Unable to find entity set");
// Get association types in which current entity's type is one of the ends.
List<AssociationSet> associations = MetadataHelper.GetAssociationsForEntitySet(entitySet);
bool skippedFK = false;
// Find key property names which are part of referential integrity constraints
foreach (AssociationSet association in associations)
{
// NOTE ReferentialConstraints collection currently can contain 0 or 1 element
if (skipFK && association.ElementType.IsForeignKey)
{
skippedFK = true;
}
else
{
foreach (ReferentialConstraint constraint in association.ElementType.ReferentialConstraints)
{
if (constraint.ToRole.TypeUsage.EdmType == entitySet.ElementType.GetReferenceType())
{
// lazy creation of the list
propertiesToRetrieve = propertiesToRetrieve ?? new List<string>();
foreach (EdmProperty property in constraint.ToProperties)
{
propertiesToRetrieve.Add(property.Name);
}
}
// There are schemas, in which relationship has the same entitySet on both ends
// that is why following 'if' statement is not inside of 'else' of previous 'if' statement
if (constraint.FromRole.TypeUsage.EdmType == entitySet.ElementType.GetReferenceType())
{
propertiesToPropagateExist = true;
}
}
}
}
return skippedFK;
}
/// <summary>
/// Helper method to validate consistency of RelationshipManager instances
/// </summary>
/// <param name="entity">entity to compare against</param>
/// <returns>True if entity is the owner of this RelationshipManager, otherwise false</returns>
internal bool IsOwner(IEntityWrapper wrappedEntity)
{
IEntityWrapper wrappedOwner = WrappedOwner;
Debug.Assert(wrappedEntity != null, "IEntityWrapper instance is null.");
return Object.ReferenceEquals(wrappedEntity.Entity, wrappedOwner.Entity);
}
/// <summary>
/// Calls AttachContext on each RelatedEnd referenced by this manager.
/// </summary>
internal void AttachContextToRelatedEnds(ObjectContext context, EntitySet entitySet, MergeOption mergeOption)
{
Debug.Assert(null != context, "context");
Debug.Assert(null != entitySet, "entitySet");
if (null != _relationships)
{
// If GetAllRelatedEnds was called while the entity was not attached to the context
// then _relationships may contain RelatedEnds that do not belong in based on the
// entity set that the owner ultimately was attached to. This means that when attaching
// we need to trim the list to get rid of those RelatedEnds.
// It is possible that the RelatedEnds may have been obtained explicitly rather than through
// GetAllRelatedEnds. If this is the case, then we prune anyway unless the RelatedEnd actually
// has something attached to it, in which case we try to attach the context which will cause
// an exception to be thrown. This is all a bit messy, but it's the best we could do given that
// GetAllRelatedEnds was implemented in 3.5sp1 without taking MEST into account.
// Note that the Relationships property makes a copy so we can modify the list while iterating
foreach (RelatedEnd relatedEnd in Relationships)
{
EdmType relationshipType;
RelationshipSet relationshipSet;
relatedEnd.FindRelationshipSet(context, entitySet, out relationshipType, out relationshipSet);
if (relationshipSet != null || !relatedEnd.IsEmpty())
{
relatedEnd.AttachContext(context, entitySet, mergeOption);
}
else
{
_relationships.Remove(relatedEnd);
}
}
}
}
/// <summary>
/// Calls AttachContext on each RelatedEnd referenced by this manager and also on all the enties
/// referenced by that related end.
/// </summary>
internal void ResetContextOnRelatedEnds(ObjectContext context, EntitySet entitySet, MergeOption mergeOption)
{
Debug.Assert(null != context, "context");
Debug.Assert(null != entitySet, "entitySet");
if (null != _relationships)
{
foreach (RelatedEnd relatedEnd in Relationships)
{
relatedEnd.AttachContext(context, entitySet, mergeOption);
foreach (IEntityWrapper wrappedEntity in relatedEnd.GetWrappedEntities())
{
wrappedEntity.ResetContext(context, relatedEnd.GetTargetEntitySetFromRelationshipSet(), mergeOption);
}
}
}
}
/// <summary>
/// Calls DetachContext on each RelatedEnd referenced by this manager.
/// </summary>
internal void DetachContextFromRelatedEnds()
{
if (null != _relationships)
{
// Not using defensive copy here since DetachContext should not cause change in underlying
// _relationships collection.
foreach (RelatedEnd relatedEnd in _relationships)
{
relatedEnd.DetachContext();
}
}
}
// --------------------
// Internal definitions
// --------------------
[Conditional("DEBUG")]
internal void VerifyIsNotRelated()
{
if (this._relationships != null)
{
foreach (var r in this._relationships)
{
if (!r.IsEmpty())
{
Debug.Assert(false, "Cannot change a state of a Deleted entity if the entity has other than deleted relationships with other entities.");
}
}
}
}
}
}
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