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//---------------------------------------------------------------------
// <copyright file="EdmType.cs" company="Microsoft">
// Copyright (c) Microsoft Corporation. All rights reserved.
// </copyright>
//
// @owner Microsoft
// @backupOwner Microsoft
//---------------------------------------------------------------------
using System.Data.Common;
using System.Globalization;
using System.Diagnostics;
using System.Collections.Generic;
using System.Text;
using System.Threading;
namespace System.Data.Metadata.Edm
{
/// <summary>
/// Base EdmType class for all the model types
/// </summary>
[System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Naming", "CA1704:IdentifiersShouldBeSpelledCorrectly", MessageId = "Edm")]
public abstract class EdmType : GlobalItem
{
#region Constructors
/// <summary>
/// Initializes a new instance of EdmType
/// </summary>
internal EdmType()
{
// No initialization of item attributes in here, it's used as a pass thru in the case for delay population
// of item attributes
}
/// <summary>
/// Constructs a new instance of EdmType with the given name, namespace and version
/// </summary>
/// <param name="name">name of the type</param>
/// <param name="namespaceName">namespace of the type</param>
/// <param name="version">version of the type</param>
/// <param name="dataSpace">dataSpace in which this edmtype belongs to</param>
/// <exception cref="System.ArgumentNullException">Thrown if either the name, namespace or version arguments are null</exception>
internal EdmType(string name,
string namespaceName,
DataSpace dataSpace)
{
EntityUtil.GenericCheckArgumentNull(name, "name");
EntityUtil.GenericCheckArgumentNull(namespaceName, "namespaceName");
// Initialize the item attributes
EdmType.Initialize(this,
name,
namespaceName,
dataSpace,
false,
null);
}
#endregion
#region Fields
private CollectionType _collectionType;
private string _identity;
private string _name;
private string _namespace;
private EdmType _baseType;
#endregion
#region Properties
/// <summary>
/// Direct accessor for the field Identity. The reason we need to do this is that for derived class,
/// they want to cache things only when they are readonly. Plus they want to check for null before
/// updating the value
/// </summary>
internal string CacheIdentity
{
get
{
return _identity;
}
private set
{
_identity = value;
}
}
/// <summary>
/// Returns the identity of the edm type
/// </summary>
internal override string Identity
{
get
{
if (this.CacheIdentity == null)
{
StringBuilder builder = new StringBuilder(50);
BuildIdentity(builder);
this.CacheIdentity = builder.ToString();
}
return this.CacheIdentity;
}
}
/// <summary>
/// Returns the name of the EdmType
/// </summary>
[MetadataProperty(PrimitiveTypeKind.String, false)]
public String Name
{
get
{
return _name;
}
internal set
{
Debug.Assert(value != null, "The name should never be set to null");
_name = value;
}
}
/// <summary>
/// Returns the namespace of the EdmType
/// </summary>
[MetadataProperty(PrimitiveTypeKind.String, false)]
public String NamespaceName
{
get
{
return _namespace;
}
internal set
{
Debug.Assert(value != null, "Namespace should never be set to null");
_namespace = value;
}
}
/// <summary>
/// Returns true if the EdmType is abstract
/// </summary>
/// <exception cref="System.InvalidOperationException">Thrown if the setter is called on instance that is in ReadOnly state</exception>
[MetadataProperty(PrimitiveTypeKind.Boolean, false)]
public bool Abstract
{
get
{
return GetFlag(MetadataFlags.IsAbstract);
}
internal set
{
SetFlag(MetadataFlags.IsAbstract, value);
}
}
/// <summary>
/// Returns the base type of the EdmType
/// </summary>
/// <exception cref="System.InvalidOperationException">Thrown if the setter is called on instance that is in ReadOnly state</exception>
/// <exception cref="System.ArgumentException">Thrown if the value passed in for setter will create a loop in the inheritance chain</exception>
[MetadataProperty(BuiltInTypeKind.EdmType, false)]
public EdmType BaseType
{
get
{
return _baseType;
}
internal set
{
Util.ThrowIfReadOnly(this);
Debug.Assert(_baseType == null, "BaseType can't be set multiple times");
// Check to make sure there won't be a loop in the inheritance
EdmType type = value;
while (type != null)
{
Debug.Assert(type != this, "Cannot set the given type as base type because it would introduce a loop in inheritance");
type = type.BaseType;
}
// Also if the base type is EntityTypeBase, make sure it doesn't have keys
Debug.Assert(value == null ||
!Helper.IsEntityTypeBase(this) ||
((EntityTypeBase)this).KeyMembers.Count == 0 ||
((EntityTypeBase)value).KeyMembers.Count == 0,
" For EntityTypeBase, both base type and derived types cannot have keys defined");
_baseType = value;
}
}
/// <summary>
/// Returns the full name of this type, which is namespace + "." + name.
/// Since the identity of all EdmTypes, except EdmFunction, is same as of that
/// of the full name, FullName just returns the identity. This property is
/// over-ridden in EdmFunctin, just to return NamespaceName + "." + Name
/// </summary>
public virtual string FullName
{
get
{
return this.Identity;
}
}
/// <summary>
/// If OSpace, return the CLR Type else null
/// </summary>
/// <exception cref="System.InvalidOperationException">Thrown if the setter is called on instance that is in ReadOnly state</exception>
internal virtual System.Type ClrType
{
get { return null; }
}
internal override void BuildIdentity(StringBuilder builder)
{
// if we already know the identity, simply append it
if (null != this.CacheIdentity)
{
builder.Append(this.CacheIdentity);
return;
}
builder.Append(CreateEdmTypeIdentity(NamespaceName, Name));
}
internal static string CreateEdmTypeIdentity(string namespaceName, string name)
{
string identity = string.Empty;
if (string.Empty != namespaceName)
{
identity = namespaceName + ".";
}
identity += name;
return identity;
}
#endregion
#region Methods
/// <summary>
/// Initialize the type. This method must be called since for bootstraping we only call the constructor.
/// This method will help us initialize the type
/// </summary>
/// <param name="edmType">The edm type to initialize with item attributes</param>
/// <param name="name">The name of this type</param>
/// <param name="namespaceName">The namespace of this type</param>
/// <param name="version">The version of this type</param>
/// <param name="dataSpace">dataSpace in which this edmtype belongs to</param>
/// <param name="isAbstract">If the type is abstract</param>
/// <param name="isSealed">If the type is sealed</param>
/// <param name="baseType">The base type for this type</param>
internal static void
Initialize(EdmType edmType,
string name,
string namespaceName,
DataSpace dataSpace,
bool isAbstract,
EdmType baseType)
{
edmType._baseType = baseType;
edmType._name = name;
edmType._namespace = namespaceName;
edmType.DataSpace = dataSpace;
edmType.Abstract = isAbstract;
}
/// <summary>
/// Overriding System.Object.ToString to provide better String representation
/// for this type.
/// </summary>
public override string ToString()
{
return this.FullName;
}
/// <summary>
/// Returns the collection type whose element type is this edm type
/// </summary>
public CollectionType GetCollectionType()
{
if (_collectionType == null)
{
Interlocked.CompareExchange<CollectionType>(ref _collectionType, new CollectionType(this), null);
}
return _collectionType;
}
/// <summary>
/// check to see if otherType is among the base types,
/// </summary>
/// <param name="otherType"></param>
/// <returns>
/// if otherType is among the base types, return true,
/// otherwise returns false.
/// when othertype is same as the current type, return false.
/// </returns>
internal virtual bool IsSubtypeOf(EdmType otherType)
{
return Helper.IsSubtypeOf(this, otherType);
}
/// <summary>
/// check to see if otherType is among the sub-types,
/// </summary>
/// <param name="otherType"></param>
/// <returns>
/// if otherType is among the sub-types, returns true,
/// otherwise returns false.
/// when othertype is same as the current type, return false.
/// </returns>
internal virtual bool IsBaseTypeOf(EdmType otherType)
{
if (otherType == null)
return false;
return otherType.IsSubtypeOf(this);
}
/// <summary>
/// Check if this type is assignable from otherType
/// </summary>
/// <param name="otherType"></param>
/// <returns></returns>
internal virtual bool IsAssignableFrom(EdmType otherType)
{
return Helper.IsAssignableFrom(this, otherType);
}
/// <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();
EdmType baseType = BaseType;
if (baseType != null)
{
baseType.SetReadOnly();
}
}
}
/// <summary>
/// Returns all facet descriptions associated with this type.
/// </summary>
/// <returns>Descriptions for all built-in facets for this type.</returns>
internal virtual IEnumerable<FacetDescription> GetAssociatedFacetDescriptions()
{
return MetadataItem.GetGeneralFacetDescriptions();
}
#endregion
}
}
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