Coverage Summary for Class: MapClearTester (com.google.common.collect.testing.testers)

1 /*
2  * Copyright (C) 2008 The Guava Authors
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  * http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 package com.google.common.collect.testing.testers;
18 
19 import static com.google.common.collect.testing.features.CollectionSize.SEVERAL;
20 import static com.google.common.collect.testing.features.CollectionSize.ZERO;
21 import static com.google.common.collect.testing.features.MapFeature.FAILS_FAST_ON_CONCURRENT_MODIFICATION;
22 import static com.google.common.collect.testing.features.MapFeature.SUPPORTS_REMOVE;
23 
24 import com.google.common.annotations.GwtCompatible;
25 import com.google.common.collect.testing.AbstractMapTester;
26 import com.google.common.collect.testing.features.CollectionSize;
27 import com.google.common.collect.testing.features.MapFeature;
28 import java.util.ConcurrentModificationException;
29 import java.util.Iterator;
30 import java.util.Map.Entry;
31 import org.junit.Ignore;
32 
33 /**
34  * A generic JUnit test which tests {@code clear()} operations on a map. Can't be invoked directly;
35  * please see {@link com.google.common.collect.testing.MapTestSuiteBuilder}.
36  *
37  * @author George van den Driessche
38  * @author Chris Povirk
39  */
40 @GwtCompatible
41 @Ignore // Affects only Android test runner, which respects JUnit 4 annotations on JUnit 3 tests.
42 public class MapClearTester<K, V> extends AbstractMapTester<K, V> {
43   @MapFeature.Require(SUPPORTS_REMOVE)
44   public void testClear() {
45     getMap().clear();
46     assertTrue("After clear(), a map should be empty.", getMap().isEmpty());
47     assertEquals(0, getMap().size());
48     assertFalse(getMap().entrySet().iterator().hasNext());
49   }
50 
51   @MapFeature.Require({FAILS_FAST_ON_CONCURRENT_MODIFICATION, SUPPORTS_REMOVE})
52   @CollectionSize.Require(SEVERAL)
53   public void testClearConcurrentWithEntrySetIteration() {
54     try {
55       Iterator<Entry<K, V>> iterator = getMap().entrySet().iterator();
56       getMap().clear();
57       iterator.next();
58       fail("Expected ConcurrentModificationException");
59     } catch (ConcurrentModificationException expected) {
60       // success
61     }
62   }
63 
64   @MapFeature.Require({FAILS_FAST_ON_CONCURRENT_MODIFICATION, SUPPORTS_REMOVE})
65   @CollectionSize.Require(SEVERAL)
66   public void testClearConcurrentWithKeySetIteration() {
67     try {
68       Iterator<K> iterator = getMap().keySet().iterator();
69       getMap().clear();
70       iterator.next();
71       fail("Expected ConcurrentModificationException");
72     } catch (ConcurrentModificationException expected) {
73       // success
74     }
75   }
76 
77   @MapFeature.Require({FAILS_FAST_ON_CONCURRENT_MODIFICATION, SUPPORTS_REMOVE})
78   @CollectionSize.Require(SEVERAL)
79   public void testClearConcurrentWithValuesIteration() {
80     try {
81       Iterator<V> iterator = getMap().values().iterator();
82       getMap().clear();
83       iterator.next();
84       fail("Expected ConcurrentModificationException");
85     } catch (ConcurrentModificationException expected) {
86       // success
87     }
88   }
89 
90   @MapFeature.Require(absent = SUPPORTS_REMOVE)
91   @CollectionSize.Require(absent = ZERO)
92   public void testClear_unsupported() {
93     try {
94       getMap().clear();
95       fail(
96           "clear() should throw UnsupportedOperation if a map does "
97               + "not support it and is not empty.");
98     } catch (UnsupportedOperationException expected) {
99     }
100     expectUnchanged();
101   }
102 
103   @MapFeature.Require(absent = SUPPORTS_REMOVE)
104   @CollectionSize.Require(ZERO)
105   public void testClear_unsupportedByEmptyCollection() {
106     try {
107       getMap().clear();
108     } catch (UnsupportedOperationException tolerated) {
109     }
110     expectUnchanged();
111   }
112 }