+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.log4j.helpers;
+
+import java.util.Enumeration;
+import java.util.NoSuchElementException;
+
+/**
+
+ An always-empty Enumerator.
+
+ @author Anders Kristensen
+ @since version 1.0
+ */
+public class NullEnumeration implements Enumeration {
+ private static final NullEnumeration instance = new NullEnumeration();
+
+ private
+ NullEnumeration() {
+ }
+
+ public static NullEnumeration getInstance() {
+ return instance;
+ }
+
+ public
+ boolean hasMoreElements() {
+ return false;
+ }
+
+ public
+ Object nextElement() {
+ throw new NoSuchElementException();
+ }
+}