Merge pull request #8 from XerProjects/nullmessagehandlerresolver

Introduced NullMessageHandlerResolver

Author: joel-jeremy

Src/Xer.Delegator/Resolvers/NullMessageHandlerResolver.cs

@@ -0,0 +1,45 @@
+using System;
+
+namespace Xer.Delegator.Resolvers
+{
+    /// <summary>
+    /// Represents an object that always returns a message handler delegate instance from 
+    /// <see cref="Xer.Delegator.NullMessageHandlerDelegate.Instance"/>.
+    /// </summary>
+    public class NullMessageHandlerResolver : IMessageHandlerResolver
+    {
+        #region Declarations
+
+        private static readonly Lazy<NullMessageHandlerResolver> _instance = new Lazy<NullMessageHandlerResolver>(() => new NullMessageHandlerResolver());
+        
+        /// <summary>
+        /// Singleton instance.
+        /// </summary>
+        public static readonly NullMessageHandlerResolver Instance = _instance.Value;
+
+        #endregion Declarations
+
+        #region Constructor
+            
+        /// <summary>
+        /// Private constructor.
+        /// </summary>
+        private NullMessageHandlerResolver() { }
+
+        #endregion Constructor
+
+        #region IMessageHandlerResolver Implementation
+
+        /// <summary>
+        /// Resolve message handler delegate instance from <see cref="Xer.Delegator.NullMessageHandlerDelegate.Instance"/>.
+        /// </summary>
+        /// <param name="messageType">Type of message.</param>
+        /// <returns>Message handler delegate instance from <see cref="Xer.Delegator.NullMessageHandlerDelegate.Instance"/>.</returns>
+        public MessageHandlerDelegate ResolveMessageHandler(Type messageType)
+        {
+            return NullMessageHandlerDelegate.Instance;
+        }
+
+        #endregion IMessageHandlerResolver Implementation
+    }
+}