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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 static org.junit.jupiter.api.Assertions.assertEquals;
20  import static org.junit.jupiter.api.Assertions.assertTrue;
21  import static org.junit.jupiter.api.Assertions.fail;
22  
23  import java.util.ArrayList;
24  import java.util.Iterator;
25  import java.util.List;
26  
27  import org.apache.commons.collections4.BulkTest;
28  import org.junit.jupiter.api.Test;
29  
30  /**
31   * Tests for IteratorIterable.
32   */
33  public class IteratorIterableTest extends BulkTest {
34  
35      private Iterator<Integer> createIterator() {
36          final List<Integer> list = new ArrayList<>();
37          list.add(Integer.valueOf(0));
38          list.add(Integer.valueOf(1));
39          list.add(Integer.valueOf(2));
40          return list.iterator();
41      }
42  
43      @Test
44      @SuppressWarnings("unused")
45      public void testIterator() {
46          final Iterator<Integer> iter = createIterator();
47          final Iterable<Number> iterable = new IteratorIterable<>(iter);
48  
49          // first use
50          verifyIteration(iterable);
51  
52          // second use
53          for (final Number actual : iterable) {
54              fail("should not be able to iterate twice");
55          }
56      }
57  
58      @Test
59      public void testMultipleUserIterator() {
60          final Iterator<Integer> iter = createIterator();
61  
62          final Iterable<Number> iterable = new IteratorIterable<>(iter, true);
63  
64          // first use
65          verifyIteration(iterable);
66  
67          // second use
68          verifyIteration(iterable);
69      }
70  
71      private void verifyIteration(final Iterable<Number> iterable) {
72          int expected = 0;
73          for (final Number actual : iterable) {
74              assertEquals(expected, actual.intValue());
75              ++expected;
76          }
77          assertTrue(expected > 0);
78      }
79  }
80