Imported Upstream version 4.0.0~alpha1

Former-commit-id: 806294f5ded97629b74c85c09952f2a74fe182d9

external/referencesource/System.IdentityModel/System/IdentityModel/Tokens/SecurityToken.cs

@@ -0,0 +1,52 @@
+//------------------------------------------------------------
+// Copyright (c) Microsoft Corporation.  All rights reserved.
+//------------------------------------------------------------
+
+namespace System.IdentityModel.Tokens
+{
+    using System.Collections.ObjectModel;
+
+    public abstract class SecurityToken
+    {
+        public abstract string Id { get; }
+        public abstract ReadOnlyCollection<SecurityKey> SecurityKeys { get; }
+        public abstract DateTime ValidFrom { get; }
+        public abstract DateTime ValidTo { get; }
+
+        public virtual bool CanCreateKeyIdentifierClause<T>() where T : SecurityKeyIdentifierClause
+        {
+            return ((typeof(T) == typeof(LocalIdKeyIdentifierClause)) && CanCreateLocalKeyIdentifierClause());
+        }
+
+        public virtual T CreateKeyIdentifierClause<T>() where T : SecurityKeyIdentifierClause
+        {
+            if ((typeof(T) == typeof(LocalIdKeyIdentifierClause)) && CanCreateLocalKeyIdentifierClause())
+                return new LocalIdKeyIdentifierClause(this.Id, this.GetType()) as T;
+
+            throw DiagnosticUtility.ExceptionUtility.ThrowHelperError(new NotSupportedException(
+                SR.GetString(SR.TokenDoesNotSupportKeyIdentifierClauseCreation, GetType().Name, typeof(T).Name)));
+        }
+
+        public virtual bool MatchesKeyIdentifierClause(SecurityKeyIdentifierClause keyIdentifierClause)
+        {
+            LocalIdKeyIdentifierClause localKeyIdentifierClause = keyIdentifierClause as LocalIdKeyIdentifierClause;
+            if (localKeyIdentifierClause != null)
+                return localKeyIdentifierClause.Matches(this.Id, this.GetType());
+
+            return false;
+        }
+
+        public virtual SecurityKey ResolveKeyIdentifierClause(SecurityKeyIdentifierClause keyIdentifierClause)
+        {
+            if (this.SecurityKeys.Count != 0 && MatchesKeyIdentifierClause(keyIdentifierClause))
+                return this.SecurityKeys[0];
+
+            return null;
+        }
+
+        bool CanCreateLocalKeyIdentifierClause()
+        {
+            return (this.Id != null);
+        }
+    }
+}