add base methods to tokenhandler

src/Microsoft.IdentityModel.JsonWebTokens/JsonWebTokenHandler.cs

@@ -137,7 +137,7 @@ public IDictionary<string, string> InboundClaimTypeMap
         /// <para>'false' if token.Length is greater than <see cref="TokenHandler.MaximumTokenSizeInBytes"/>.</para>
         /// <para>'true' if the token is in JSON compact serialization format.</para>
         /// </returns>
-        public virtual bool CanReadToken(string token)
+        public override bool CanReadToken(string token)
         {
             if (string.IsNullOrWhiteSpace(token))
                 return false;

src/Microsoft.IdentityModel.Tokens/SecurityTokenHandler.cs

@@ -79,17 +79,6 @@ public virtual bool CanReadToken(XmlReader reader)
             return false;
         }
 
-        /// <summary>
-        /// Indicates whether the current token string can be read as a token 
-        /// of the type handled by this instance.
-        /// </summary>
-        /// <param name="tokenString">The token string thats needs to be read.</param>
-        /// <returns>'True' if the ReadToken method can parse the token string.</returns>
-        public virtual bool CanReadToken(string tokenString)
-        {
-            return false;
-        }
-
         /// <summary>
         /// Gets security token.
         /// </summary>

src/Microsoft.IdentityModel.Tokens/TokenHandler.cs

@@ -5,6 +5,7 @@
 using System;
 using System.ComponentModel;
 using System.Security.Claims;
+using System.Text.Json;
 using System.Threading.Tasks;
 using static Microsoft.IdentityModel.Logging.LogHelper;
 
@@ -75,6 +76,28 @@ public int TokenLifetimeInMinutes
         /// <returns>A <see cref="TokenValidationResult"/></returns>
         public virtual Task<TokenValidationResult> ValidateTokenAsync(SecurityToken token, TokenValidationParameters validationParameters) => throw new NotImplementedException();
 
+        /// <summary>
+        /// Indicates whether the current token string can be read as a token 
+        /// of the type handled by this instance.
+        /// </summary>
+        /// <param name="tokenString">The token string thats needs to be read.</param>
+        /// <returns>'True' if the ReadToken method can parse the token string.</returns>
+        public virtual bool CanReadToken(string tokenString) => false;
+
+        /// <summary>
+        /// Creates a <see cref="SecurityToken"/> as a <see cref="string"/> as described by the provided <see cref="SecurityTokenDescriptor"/>.
+        /// </summary>
+        /// <param name="tokenDescriptor">The <see cref="SecurityTokenDescriptor"/> used to create the token.</param>
+        /// <returns>A <see cref="string"/>.</returns>
+        /// <exception cref="NotImplementedException"></exception>
+        public virtual string CreateSecurityTokenAsString(SecurityTokenDescriptor tokenDescriptor) => throw new NotImplementedException();
+
+        /// <summary>
+        /// Creates a <see cref="SecurityToken"/> as described by the provided <see cref="SecurityTokenDescriptor"/>.
+        /// </summary>
+        /// <param name="tokenDescriptor"><see cref="SecurityTokenDescriptor"/></param>
+        public virtual SecurityToken CreateSecurityToken(SecurityTokenDescriptor tokenDescriptor) => throw new NotImplementedException();
+
         /// <summary>
         /// Converts a string into an instance of <see cref="SecurityToken"/>.
         /// </summary>

test/Microsoft.IdentityModel.JsonWebTokens.Tests/json/JsonWebTokenHandler.cs

@@ -152,7 +152,7 @@ internal static IDictionary<string, object> AddCtyClaimDefaultValue(IDictionary<
         /// <para>'false' if token.Length is greater than <see cref="TokenHandler.MaximumTokenSizeInBytes"/>.</para>
         /// <para>'true' if the token is in JSON compact serialization format.</para>
         /// </returns>
-        public virtual bool CanReadToken(string token)
+        public override bool CanReadToken(string token)
         {
             if (string.IsNullOrWhiteSpace(token))
                 return false;