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.CollectionFeature.ALLOWS_NULL_QUERIES; 20 import static com.google.common.collect.testing.features.CollectionFeature.ALLOWS_NULL_VALUES; 21 import static com.google.common.collect.testing.features.CollectionFeature.FAILS_FAST_ON_CONCURRENT_MODIFICATION; 22 import static com.google.common.collect.testing.features.CollectionFeature.SUPPORTS_REMOVE; 23 import static com.google.common.collect.testing.features.CollectionSize.SEVERAL; 24 import static com.google.common.collect.testing.features.CollectionSize.ZERO; 25 26 import com.google.common.annotations.GwtCompatible; 27 import com.google.common.collect.testing.AbstractCollectionTester; 28 import com.google.common.collect.testing.WrongType; 29 import com.google.common.collect.testing.features.CollectionFeature; 30 import com.google.common.collect.testing.features.CollectionSize; 31 32 import java.util.ConcurrentModificationException; 33 import java.util.Iterator; 34 35 /** 36 * A generic JUnit test which tests {@code remove} operations on a collection. 37 * Can't be invoked directly; please see 38 * {@link com.google.common.collect.testing.CollectionTestSuiteBuilder}. 39 * 40 * @author George van den Driessche 41 */ 42 @SuppressWarnings("unchecked") // too many "unchecked generic array creations" 43 @GwtCompatible 44 public class CollectionRemoveTester<E> extends AbstractCollectionTester<E> { 45 @CollectionFeature.Require(SUPPORTS_REMOVE) 46 @CollectionSize.Require(absent = ZERO) 47 public void testRemove_present() { 48 int initialSize = collection.size(); 49 assertTrue("remove(present) should return true", 50 collection.remove(samples.e0)); 51 assertEquals("remove(present) should decrease a collection's size by one.", 52 initialSize - 1, collection.size()); 53 expectMissing(samples.e0); 54 } 55 56 @CollectionFeature.Require({SUPPORTS_REMOVE, 57 FAILS_FAST_ON_CONCURRENT_MODIFICATION}) 58 @CollectionSize.Require(SEVERAL) 59 public void testRemovePresentConcurrentWithIteration() { 60 try { 61 Iterator<E> iterator = collection.iterator(); 62 assertTrue(collection.remove(samples.e0)); 63 iterator.next(); 64 fail("Expected ConcurrentModificationException"); 65 } catch (ConcurrentModificationException expected) { 66 // success 67 } 68 } 69 70 @CollectionFeature.Require(SUPPORTS_REMOVE) 71 public void testRemove_notPresent() { 72 assertFalse("remove(notPresent) should return false", 73 collection.remove(samples.e3)); 74 expectUnchanged(); 75 } 76 77 @CollectionFeature.Require({SUPPORTS_REMOVE, ALLOWS_NULL_VALUES}) 78 @CollectionSize.Require(absent = ZERO) 79 public void testRemove_nullPresent() { 80 collection = getSubjectGenerator().create(createArrayWithNullElement()); 81 82 int initialSize = collection.size(); 83 assertTrue("remove(null) should return true", collection.remove(null)); 84 assertEquals("remove(present) should decrease a collection's size by one.", 85 initialSize - 1, collection.size()); 86 expectMissing((E) null); 87 } 88 89 @CollectionFeature.Require(absent = SUPPORTS_REMOVE) 90 @CollectionSize.Require(absent = ZERO) 91 public void testRemove_unsupported() { 92 try { 93 collection.remove(samples.e0); 94 fail("remove(present) should throw UnsupportedOperationException"); 95 } catch (UnsupportedOperationException expected) { 96 } 97 expectUnchanged(); 98 assertTrue("remove(present) should not remove the element", 99 collection.contains(samples.e0)); 100 } 101 102 @CollectionFeature.Require(absent = SUPPORTS_REMOVE) 103 public void testRemove_unsupportedNotPresent() { 104 try { 105 assertFalse("remove(notPresent) should return false or throw " 106 + "UnsupportedOperationException", 107 collection.remove(samples.e3)); 108 } catch (UnsupportedOperationException tolerated) { 109 } 110 expectUnchanged(); 111 expectMissing(samples.e3); 112 } 113 114 @CollectionFeature.Require( 115 value = SUPPORTS_REMOVE, 116 absent = ALLOWS_NULL_QUERIES) 117 public void testRemove_nullNotSupported() { 118 try { 119 assertFalse("remove(null) should return false or throw " 120 + "NullPointerException", 121 collection.remove(null)); 122 } catch (NullPointerException tolerated) { 123 } 124 expectUnchanged(); 125 } 126 127 @CollectionFeature.Require({SUPPORTS_REMOVE, ALLOWS_NULL_QUERIES}) 128 public void testRemove_nullAllowed() { 129 assertFalse("remove(null) should return false", collection.remove(null)); 130 expectUnchanged(); 131 } 132 133 @CollectionFeature.Require(absent = SUPPORTS_REMOVE) 134 @CollectionSize.Require(absent = ZERO) 135 public void testIteratorRemove_unsupported() { 136 Iterator<E> iterator = collection.iterator(); 137 iterator.next(); 138 try { 139 iterator.remove(); 140 fail("iterator.remove() should throw UnsupportedOperationException"); 141 } catch (UnsupportedOperationException expected) { 142 } 143 expectUnchanged(); 144 assertTrue(collection.contains(samples.e0)); 145 } 146 147 @CollectionFeature.Require(SUPPORTS_REMOVE) 148 public void testRemove_wrongType() { 149 try { 150 assertFalse(collection.remove(WrongType.VALUE)); 151 } catch (ClassCastException tolerated) { 152 } 153 expectUnchanged(); 154 } 155 } 156
