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1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one or more
3    * contributor license agreements.  See the NOTICE file distributed with
4    * this work for additional information regarding copyright ownership.
5    * The ASF licenses this file to You under the Apache License, Version 2.0
6    * (the "License"); you may not use this file except in compliance with
7    * the License.  You may obtain a copy of the License at
8    *
9    *      http://www.apache.org/licenses/LICENSE-2.0
10   *
11   * Unless required by applicable law or agreed to in writing, software
12   * distributed under the License is distributed on an "AS IS" BASIS,
13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14   * See the License for the specific language governing permissions and
15   * limitations under the License.
16   */
17  package org.apache.commons.collections4.iterators;
18  
19  import org.apache.commons.collections4.OrderedIterator;
20  import org.apache.commons.collections4.ResettableIterator;
21  
22  /**
23   * Provides an implementation of an empty ordered iterator.
24   *
25   * @param <E> the type of elements returned by this iterator.
26   * @since 3.1
27   */
28  public class EmptyOrderedIterator<E> extends AbstractEmptyIterator<E>
29          implements OrderedIterator<E>, ResettableIterator<E> {
30  
31      /**
32       * Singleton instance of the iterator.
33       * @since 3.1
34       */
35      @SuppressWarnings("rawtypes")
36      public static final OrderedIterator INSTANCE = new EmptyOrderedIterator<>();
37  
38      /**
39       * Typed instance of the iterator.
40       * @param <E> the element type
41       * @return OrderedIterator&lt;E&gt;
42       */
43      public static <E> OrderedIterator<E> emptyOrderedIterator() {
44          return INSTANCE;
45      }
46  
47      /**
48       * Constructs a new instance.
49       */
50      protected EmptyOrderedIterator() {
51      }
52  
53  }