1 /*
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3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
12  * version 2 for more details (a copy is included in the LICENSE file that
13  * accompanied this code).
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23 
24 /*
25  * @test
26  * @bug 6323374
27  * @run testng WrappedUnmodifiableCollections
28  */
29 
30 package test.java.util.Collections;
31 
32 import java.util.*;
33 import java.util.function.Function;
34 import org.testng.annotations.Test;
35 import static org.testng.Assert.*;
36 
37 
38 @Test
39 public class WrappedUnmodifiableCollections {
40 
testWrapping(T collection, Function<T,E> wrapper)41     private static <T,E extends T> void testWrapping(T collection, Function<T,E> wrapper) {
42         var collection1 = wrapper.apply(collection);
43         var collection2 = wrapper.apply(collection1);
44         assertNotSame(collection, collection2);
45         assertSame(collection1, collection2);
46     }
47 
testUnmodifiableListsDontWrap()48     public void testUnmodifiableListsDontWrap() {
49         List<List<?>> lists = List.of(List.of(), List.of(1,2,3), List.of(1),
50                 List.of(1,2,3,4,5,6),
51                 List.of(1,2,3).subList(0,1),
52                 new LinkedList<>(List.of(1,2,3)),
53                 new ArrayList<>(List.of(1,2,3)));
54 
55         for(List<?> list : lists) {
56             testWrapping(list, Collections::unmodifiableList);
57         }
58     }
59 
testUnmodifiableCollectionsDontWrap()60     public void testUnmodifiableCollectionsDontWrap() {
61         Collection<?> list = List.of();
62         testWrapping(list, Collections::unmodifiableCollection);
63     }
64 
testUnmodifiableSetsDontWrap()65     public void testUnmodifiableSetsDontWrap() {
66 
67         List<Set<?>> sets = List.of(new TreeSet<>(),
68                                     Set.of(1, 2),
69                                     Set.of(1,2,3,4,5,6));
70 
71         for (Set<?> set : sets) {
72             testWrapping(set, Collections::unmodifiableSet);
73         }
74 
75         TreeSet<?> treeSet = new TreeSet<>();
76 
77         //Collections.UnmodifiableSortedSet
78         testWrapping((SortedSet<?>) treeSet, Collections::unmodifiableSortedSet);
79 
80         //Collections.UnmodifiableNavigableSet
81         testWrapping((NavigableSet<?>) treeSet, Collections::unmodifiableNavigableSet);
82 
83     }
84 
testUnmodifiableMapsDontWrap()85     public void testUnmodifiableMapsDontWrap() {
86         TreeMap<?,?> treeMap = new TreeMap<>();
87 
88         List<Map<?,?>> maps = List.of(treeMap,
89                 Map.of(1,1),
90                 Map.of(1, 1, 2, 2, 3, 3, 4, 4));
91 
92         for (Map<?,?> map : maps) {
93             testWrapping(map, Collections::unmodifiableMap);
94         }
95 
96         //Collections.UnModifiableSortedMap
97         testWrapping((SortedMap<?,?>) treeMap, Collections::unmodifiableSortedMap);
98 
99         //Collections.UnModifiableNavigableMap
100         testWrapping((NavigableMap<?,?>) treeMap, Collections::unmodifiableNavigableMap);
101 
102     }
103 
104 }
105