Initial Commit

iTechSharp/srcbc/util/collections/EmptyEnumerable.cs

@@ -0,0 +1,44 @@
+using System;
+using System.Collections;
+
+namespace Org.BouncyCastle.Utilities.Collections
+{
+	public sealed class EmptyEnumerable
+		: IEnumerable
+	{
+		public static readonly IEnumerable Instance = new EmptyEnumerable();
+
+		private EmptyEnumerable()
+		{
+		}
+
+		public IEnumerator GetEnumerator()
+		{
+			return EmptyEnumerator.Instance;
+		}
+	}
+
+	public sealed class EmptyEnumerator
+		: IEnumerator
+	{
+		public static readonly IEnumerator Instance = new EmptyEnumerator();
+
+		private EmptyEnumerator()
+		{
+		}
+
+		public bool MoveNext()
+		{
+			return false;
+		}
+
+		public void Reset()
+		{
+		}
+
+		public object Current
+		{
+			get { throw new InvalidOperationException("No elements"); }
+		}
+	}
+}