Imported Upstream version 4.6.0.125

Former-commit-id: a2155e9bd80020e49e72e86c44da02a8ac0e57a4

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

@@ -0,0 +1,165 @@
+//---------------------------------------------------------------------
+// <copyright file="MetadataProperty.cs" company="Microsoft">
+//      Copyright (c) Microsoft Corporation.  All rights reserved.
+// </copyright>
+//
+// @owner       [....]
+// @backupOwner [....]
+//---------------------------------------------------------------------
+
+using System;
+using System.Collections.Generic;
+using System.Data.Common;
+using System.Diagnostics;
+using System.Reflection;
+
+namespace System.Data.Metadata.Edm
+{
+    /// <summary>
+    /// Class representing a metadata attribute for an item
+    /// </summary>
+    public sealed class MetadataProperty : MetadataItem
+    {
+        #region Constructors
+        /// <summary>
+        /// The constructor for MetadataProperty taking in a name, a TypeUsage object, and a value for the attribute
+        /// </summary>
+        /// <param name="name">The name of this MetadataProperty</param>
+        /// <param name="typeUsage">The TypeUsage describing the type of this MetadataProperty</param>
+        /// <param name="value">The value for this attribute</param>
+        /// <exception cref="System.ArgumentNullException">Thrown if typeUsage argument is null</exception>
+        internal MetadataProperty(string name, TypeUsage typeUsage, object value)
+        {
+            EntityUtil.GenericCheckArgumentNull(typeUsage, "typeUsage");
+
+            _name = name;
+            _value = value;
+            _typeUsage = typeUsage;
+            _propertyKind = PropertyKind.Extended;
+        }
+
+        /// <summary>
+        /// The constructor for MetadataProperty taking in all the ingredients for creating TypeUsage and the actual value
+        /// </summary>
+        /// <param name="name">The name of the attribute</param>
+        /// <param name="edmType">The edm type of the attribute</param>
+        /// <param name="isCollectionType">Whether the collection type of the given edm type should be used</param>
+        /// <param name="value">The value of the attribute</param>
+        internal MetadataProperty(string name, EdmType edmType, bool isCollectionType, object value)
+        {
+            EntityUtil.CheckArgumentNull(edmType, "edmType");
+
+            _name = name;
+            _value = value;
+            if (isCollectionType)
+            {
+                _typeUsage = TypeUsage.Create(edmType.GetCollectionType());
+            }
+            else
+            {
+                _typeUsage = TypeUsage.Create(edmType);
+            }
+            _propertyKind = PropertyKind.System;
+        }
+        #endregion
+
+        #region Fields
+        private string _name;
+        private PropertyKind _propertyKind;
+        private object _value;
+        private TypeUsage _typeUsage;
+        #endregion
+
+        #region Properties
+        /// <summary>
+        /// Returns the kind of the type
+        /// </summary>
+        public override BuiltInTypeKind BuiltInTypeKind { get { return BuiltInTypeKind.MetadataProperty; } }
+
+        /// <summary>
+        /// Gets the identity of this item
+        /// </summary>
+        internal override string Identity
+        {
+            get
+            {
+                return Name;
+            }
+        }
+
+        /// <summary>
+        /// Gets/Sets the name of this MetadataProperty
+        /// </summary>
+        [MetadataProperty(PrimitiveTypeKind.String, false)]
+        public string Name
+        {
+            get
+            {
+                // The name is immutable, so it should be safe to always get it from the field
+                return _name;
+            }
+        }
+
+        /// <summary>
+        /// Gets/Sets the value of this MetadataProperty
+        /// </summary>
+        /// <exception cref="System.InvalidOperationException">Thrown if the MetadataProperty instance is in readonly state</exception>
+        [MetadataProperty(typeof(Object), false)]
+        public object Value
+        {
+            get
+            {
+                // Check if we're redirecting to an MetadataItem system property
+                MetadataPropertyValue redirectValue = _value as MetadataPropertyValue;
+                if (null != redirectValue)
+                {
+                    return redirectValue.GetValue();
+                }
+
+                // If not, return the actual stored value
+                return _value;
+            }
+        }
+
+        /// <summary>
+        /// Gets/Sets the TypeUsage object describing the type of this attribute
+        /// </summary>
+        /// <exception cref="System.ArgumentNullException">Thrown if value passed into setter is null</exception>
+        /// <exception cref="System.InvalidOperationException">Thrown if the MetadataProperty instance is in readonly state</exception>
+        [MetadataProperty(BuiltInTypeKind.TypeUsage, false)]
+        public TypeUsage TypeUsage
+        {
+            get
+            {
+                return _typeUsage;
+            }
+        }
+        #endregion
+
+        #region Methods
+        /// <summary>
+        /// Sets this item to be readonly, once this is set, the item will never be writable again.
+        /// </summary>
+        internal override void SetReadOnly()
+        {
+            if (!IsReadOnly)
+            {
+                base.SetReadOnly();
+
+                // TypeUsage is always readonly, no need to set _typeUsage
+            }
+        }
+
+        /// <summary>
+        /// Returns the kind of the attribute
+        /// </summary>
+        public PropertyKind PropertyKind
+        {
+            get
+            {
+                return _propertyKind;
+            }
+        }
+        #endregion
+    }
+}