Imported Upstream version 4.6.0.125

Former-commit-id: a2155e9bd80020e49e72e86c44da02a8ac0e57a4

mcs/class/referencesource/System.Data.Entity/System/Data/Metadata/Edm/EntitySet.cs

@@ -0,0 +1,173 @@
+//---------------------------------------------------------------------
+// <copyright file="EntitySet.cs" company="Microsoft">
+//      Copyright (c) Microsoft Corporation.  All rights reserved.
+// </copyright>
+//
+// @owner       [....]
+// @backupOwner [....]
+//---------------------------------------------------------------------
+
+using System;
+using System.Collections.Generic;
+using System.Text;
+using System.Diagnostics;
+using System.Threading;
+using System.Data.Common.Utils;
+using System.Collections.ObjectModel;
+
+namespace System.Data.Metadata.Edm
+{
+    /// <summary>
+    /// concrete Class for representing a entity set
+    /// </summary>
+    public class EntitySet : EntitySetBase
+    {
+        #region Constructors
+        /// <summary>
+        /// The constructor for constructing the EntitySet with a given name and an entity type
+        /// </summary>
+        /// <param name="name">The name of the EntitySet</param>
+        /// <param name="schema">The db schema</param>
+        /// <param name="table">The db table</param>
+        /// <param name="definingQuery">The provider specific query that should be used to retrieve the EntitySet</param>
+        /// <param name="entityType">The entity type of the entities that this entity set type contains</param> 
+        /// <exception cref="System.ArgumentNullException">Thrown if the argument name or entityType is null</exception>
+        internal EntitySet(string name, string schema, string table, string definingQuery, EntityType entityType)
+            : base(name, schema, table, definingQuery, entityType)
+        {
+        }
+        #endregion
+
+        #region Fields
+        private ReadOnlyCollection<Tuple<AssociationSet, ReferentialConstraint>> _foreignKeyDependents;
+        private ReadOnlyCollection<Tuple<AssociationSet, ReferentialConstraint>> _foreignKeyPrincipals;
+        private volatile bool _hasForeignKeyRelationships;
+        private volatile bool _hasIndependentRelationships;
+        #endregion
+
+        #region Properties
+        /// <summary>
+        /// Returns the kind of the type
+        /// </summary>
+        public override BuiltInTypeKind BuiltInTypeKind { get { return BuiltInTypeKind.EntitySet; } }
+
+        /// <summary>
+        /// Gets/Sets the entity type of this entity set
+        /// </summary>
+        public new EntityType ElementType
+        {
+            get
+            {
+                return (EntityType)base.ElementType;
+            }
+        }
+
+        /// <summary>
+        /// Returns the associations and constraints where "this" EntitySet particpates as the Principal end. 
+        /// From the results of this list, you can retrieve the Dependent IRelatedEnds
+        /// </summary>
+        internal ReadOnlyCollection<Tuple<AssociationSet, ReferentialConstraint>> ForeignKeyDependents
+        {
+            get
+            {
+                if (_foreignKeyDependents == null)
+                {
+                    InitializeForeignKeyLists();
+                }
+                return _foreignKeyDependents;
+            }
+        }
+
+        /// <summary>
+        /// Returns the associations and constraints where "this" EntitySet particpates as the Dependent end. 
+        /// From the results of this list, you can retrieve the Principal IRelatedEnds
+        /// </summary>
+        internal ReadOnlyCollection<Tuple<AssociationSet, ReferentialConstraint>> ForeignKeyPrincipals
+        {
+            get
+            {
+                if (_foreignKeyPrincipals == null)
+                {
+                    InitializeForeignKeyLists();
+                }
+                return _foreignKeyPrincipals;
+            }
+        }
+
+        /// <summary>
+        /// True if this entity set participates in any foreign key relationships, otherwise false.
+        /// </summary>
+        internal bool HasForeignKeyRelationships
+        {
+            get
+            {
+                if (_foreignKeyPrincipals == null)
+                {
+                    InitializeForeignKeyLists();
+                }
+                return _hasForeignKeyRelationships;
+            }
+        }
+
+        /// <summary>
+        /// True if this entity set participates in any independent relationships, otherwise false.
+        /// </summary>
+        internal bool HasIndependentRelationships
+        {
+            get
+            {
+                if (_foreignKeyPrincipals == null)
+                {
+                    InitializeForeignKeyLists();
+                }
+                return _hasIndependentRelationships;
+            }
+        }
+
+        #endregion
+
+        #region Methods
+        private void InitializeForeignKeyLists()
+        {
+            var dependents = new List<Tuple<AssociationSet, ReferentialConstraint>>();
+            var principals = new List<Tuple<AssociationSet, ReferentialConstraint>>();
+            bool foundFkRelationship = false;
+            bool foundIndependentRelationship = false;
+            foreach (AssociationSet associationSet in MetadataHelper.GetAssociationsForEntitySet(this))
+            {
+                if (associationSet.ElementType.IsForeignKey)
+                {
+                    foundFkRelationship = true;
+                    Debug.Assert(associationSet.ElementType.ReferentialConstraints.Count == 1, "Expected exactly one constraint for FK");
+                    ReferentialConstraint constraint = associationSet.ElementType.ReferentialConstraints[0];
+                    if (constraint.ToRole.GetEntityType().IsAssignableFrom(this.ElementType) ||
+                        this.ElementType.IsAssignableFrom(constraint.ToRole.GetEntityType()))
+                    {
+                        // Dependents
+                        dependents.Add(new Tuple<AssociationSet, ReferentialConstraint>(associationSet, constraint));
+                    }
+                    if (constraint.FromRole.GetEntityType().IsAssignableFrom(this.ElementType) ||
+                        this.ElementType.IsAssignableFrom(constraint.FromRole.GetEntityType()))
+                    {
+                        // Principals
+                        principals.Add(new Tuple<AssociationSet, ReferentialConstraint>(associationSet, constraint));
+                    }
+                }
+                else
+                {
+                    foundIndependentRelationship = true;
+                }
+            }
+
+            _hasForeignKeyRelationships = foundFkRelationship;
+            _hasIndependentRelationships = foundIndependentRelationship;
+
+            var readOnlyDependents = dependents.AsReadOnly();
+            var readOnlyPrincipals = principals.AsReadOnly();
+
+            Interlocked.CompareExchange(ref _foreignKeyDependents, readOnlyDependents, null);
+            Interlocked.CompareExchange(ref _foreignKeyPrincipals, readOnlyPrincipals, null);
+        }
+        #endregion
+    }
+}