Imported Upstream version 4.6.0.125

Former-commit-id: a2155e9bd80020e49e72e86c44da02a8ac0e57a4

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

@@ -0,0 +1,204 @@
+//---------------------------------------------------------------------
+// <copyright file="Facet.cs" company="Microsoft">
+//      Copyright (c) Microsoft Corporation.  All rights reserved.
+// </copyright>
+//
+// @owner       [....]
+// @backupOwner [....]
+//---------------------------------------------------------------------
+
+namespace System.Data.Metadata.Edm
+{
+    using System;
+    using System.Diagnostics;
+    using System.Globalization;
+
+    /// <summary>
+    /// Class for representing a Facet object
+    /// This object is Immutable (not just set to readonly) and 
+    /// some parts of the system are depending on that behavior
+    /// </summary>
+    [DebuggerDisplay("{Name,nq}={Value}")]
+    public sealed class Facet : MetadataItem
+    {
+        #region Constructors
+        
+        /// <summary>
+        /// The constructor for constructing a Facet object with the facet description and a value
+        /// </summary>
+        /// <param name="facetDescription">The object describing this facet</param>
+        /// <param name="value">The value of the facet</param>
+        /// <exception cref="System.ArgumentNullException">Thrown if facetDescription argument is null</exception>
+        private Facet(FacetDescription facetDescription, object value)
+            :base(MetadataFlags.Readonly)
+        {
+            EntityUtil.GenericCheckArgumentNull(facetDescription, "facetDescription");
+
+            _facetDescription = facetDescription;
+            _value = value;
+        }
+        
+        /// <summary>
+        /// Creates a Facet instance with the specified value for the given 
+        /// facet description.
+        /// </summary>
+        /// <param name="facetDescription">The object describing this facet</param>
+        /// <param name="value">The value of the facet</param>
+        /// <exception cref="System.ArgumentNullException">Thrown if facetDescription argument is null</exception>
+        internal static Facet Create(FacetDescription facetDescription, object value)
+        {
+            return Create(facetDescription, value, false);
+        }
+
+        /// <summary>
+        /// Creates a Facet instance with the specified value for the given 
+        /// facet description.
+        /// </summary>
+        /// <param name="facetDescription">The object describing this facet</param>
+        /// <param name="value">The value of the facet</param>
+        /// <param name="bypassKnownValues">true to bypass caching and known values; false otherwise.</param>
+        /// <exception cref="System.ArgumentNullException">Thrown if facetDescription argument is null</exception>
+        internal static Facet Create(FacetDescription facetDescription, object value, bool bypassKnownValues)
+        {
+            EntityUtil.CheckArgumentNull(facetDescription, "facetDescription");
+
+            if (!bypassKnownValues)
+            {
+                // Reuse facets with a null value.
+                if (object.ReferenceEquals(value, null))
+                {
+                    return facetDescription.NullValueFacet;
+                }
+
+                // Reuse facets with a default value.
+                if (object.Equals(facetDescription.DefaultValue, value))
+                {
+                    return facetDescription.DefaultValueFacet;
+                }
+
+                // Special case boolean facets.
+                if (facetDescription.FacetType.Identity == "Edm.Boolean")
+                {
+                    bool boolValue = (bool)value;
+                    return facetDescription.GetBooleanFacet(boolValue);
+                }
+            }
+
+            Facet result = new Facet(facetDescription, value);
+
+            // Check the type of the value only if we know what the correct CLR type is
+            if (value != null && !Helper.IsUnboundedFacetValue(result) && !Helper.IsVariableFacetValue(result) && result.FacetType.ClrType != null)
+            {
+                Type valueType = value.GetType();
+                Debug.Assert(
+                    valueType == result.FacetType.ClrType 
+                    || result.FacetType.ClrType.IsAssignableFrom(valueType),
+                    string.Format(CultureInfo.CurrentCulture, "The facet {0} has type {1}, but a value of type {2} was supplied.", result.Name, result.FacetType.ClrType, valueType)
+                );
+            }
+
+            return result;
+        }
+        
+        #endregion
+
+        #region Fields
+        
+        /// <summary>The object describing this facet.</summary>
+        private readonly FacetDescription _facetDescription;
+        
+        /// <summary>The value assigned to this facet.</summary>
+        private readonly object _value;
+        
+        #endregion
+
+        #region Properties
+
+        /// <summary>
+        /// Returns the kind of the type
+        /// </summary>
+        public override BuiltInTypeKind BuiltInTypeKind { get { return BuiltInTypeKind.Facet; } }
+
+        /// <summary>
+        /// Gets the description object for describing the facet
+        /// </summary>
+        public FacetDescription Description
+        {
+            get
+            {
+                return _facetDescription;
+            }
+        }
+
+        /// <summary>
+        /// Gets/Sets the name of the facet
+        /// </summary>
+        [MetadataProperty(PrimitiveTypeKind.String, false)]
+        public String Name
+        {
+            get
+            {
+                return _facetDescription.FacetName;
+            }
+        }
+
+        /// <summary>
+        /// Gets/Sets the type of the facet
+        /// </summary>
+        [MetadataProperty(BuiltInTypeKind.EdmType, false)]
+        public EdmType FacetType
+        {
+            get
+            {
+                return _facetDescription.FacetType;
+            }
+        }
+
+        /// <summary>
+        /// Gets/Sets the value of the facet
+        /// </summary>
+        /// <exception cref="System.InvalidOperationException">Thrown if the Facet instance is in ReadOnly state</exception>
+        [MetadataProperty(typeof(Object), false)]
+        public Object Value
+        {
+            get
+            {
+                return _value;
+            }
+        }
+
+        /// <summary>
+        /// Gets the identity for this item as a string
+        /// </summary>
+        internal override string Identity
+        {
+            get
+            {
+                return _facetDescription.FacetName;
+            }
+        }
+
+        /// <summary>
+        /// Indicates whether the value of the facet is unbounded
+        /// </summary>
+        public bool IsUnbounded
+        {
+            get
+            {
+                return object.ReferenceEquals(Value, EdmConstants.UnboundedValue);
+            }
+        }
+        #endregion
+
+        #region Methods
+        /// <summary>
+        /// Overriding System.Object.ToString to provide better String representation 
+        /// for this type.
+        /// </summary>
+        public override string ToString()
+        {
+            return this.Name;
+        }
+        #endregion
+    }
+}