001/* 002 * Copyright (C) 2008 The Guava Authors 003 * 004 * Licensed under the Apache License, Version 2.0 (the "License"); 005 * you may not use this file except in compliance with the License. 006 * You may obtain a copy of the License at 007 * 008 * http://www.apache.org/licenses/LICENSE-2.0 009 * 010 * Unless required by applicable law or agreed to in writing, software 011 * distributed under the License is distributed on an "AS IS" BASIS, 012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 013 * See the License for the specific language governing permissions and 014 * limitations under the License. 015 */ 016 017package com.google.common.collect.testing.testers; 018 019import static com.google.common.collect.testing.features.CollectionFeature.ALLOWS_NULL_QUERIES; 020import static com.google.common.collect.testing.features.CollectionFeature.ALLOWS_NULL_VALUES; 021import static com.google.common.collect.testing.features.CollectionFeature.FAILS_FAST_ON_CONCURRENT_MODIFICATION; 022import static com.google.common.collect.testing.features.CollectionFeature.SUPPORTS_REMOVE; 023import static com.google.common.collect.testing.features.CollectionSize.SEVERAL; 024import static com.google.common.collect.testing.features.CollectionSize.ZERO; 025 026import com.google.common.annotations.GwtCompatible; 027import com.google.common.collect.testing.AbstractCollectionTester; 028import com.google.common.collect.testing.WrongType; 029import com.google.common.collect.testing.features.CollectionFeature; 030import com.google.common.collect.testing.features.CollectionSize; 031import java.util.ConcurrentModificationException; 032import java.util.Iterator; 033import org.junit.Ignore; 034 035/** 036 * A generic JUnit test which tests {@code remove} operations on a collection. Can't be invoked 037 * directly; please see {@link com.google.common.collect.testing.CollectionTestSuiteBuilder}. 038 * 039 * @author George van den Driessche 040 */ 041@SuppressWarnings("unchecked") // too many "unchecked generic array creations" 042@GwtCompatible 043@Ignore // Affects only Android test runner, which respects JUnit 4 annotations on JUnit 3 tests. 044public class CollectionRemoveTester<E> extends AbstractCollectionTester<E> { 045 @CollectionFeature.Require(SUPPORTS_REMOVE) 046 @CollectionSize.Require(absent = ZERO) 047 public void testRemove_present() { 048 int initialSize = collection.size(); 049 assertTrue("remove(present) should return true", collection.remove(e0())); 050 assertEquals( 051 "remove(present) should decrease a collection's size by one.", 052 initialSize - 1, 053 collection.size()); 054 expectMissing(e0()); 055 } 056 057 @CollectionFeature.Require({SUPPORTS_REMOVE, FAILS_FAST_ON_CONCURRENT_MODIFICATION}) 058 @CollectionSize.Require(SEVERAL) 059 public void testRemovePresentConcurrentWithIteration() { 060 try { 061 Iterator<E> iterator = collection.iterator(); 062 assertTrue(collection.remove(e0())); 063 iterator.next(); 064 fail("Expected ConcurrentModificationException"); 065 } catch (ConcurrentModificationException expected) { 066 // success 067 } 068 } 069 070 @CollectionFeature.Require(SUPPORTS_REMOVE) 071 public void testRemove_notPresent() { 072 assertFalse("remove(notPresent) should return false", collection.remove(e3())); 073 expectUnchanged(); 074 } 075 076 @CollectionFeature.Require({SUPPORTS_REMOVE, ALLOWS_NULL_VALUES}) 077 @CollectionSize.Require(absent = ZERO) 078 public void testRemove_nullPresent() { 079 collection = getSubjectGenerator().create(createArrayWithNullElement()); 080 081 int initialSize = collection.size(); 082 assertTrue("remove(null) should return true", collection.remove(null)); 083 assertEquals( 084 "remove(present) should decrease a collection's size by one.", 085 initialSize - 1, 086 collection.size()); 087 expectMissing((E) null); 088 } 089 090 @CollectionFeature.Require(absent = SUPPORTS_REMOVE) 091 @CollectionSize.Require(absent = ZERO) 092 public void testRemove_unsupported() { 093 try { 094 collection.remove(e0()); 095 fail("remove(present) should throw UnsupportedOperationException"); 096 } catch (UnsupportedOperationException expected) { 097 } 098 expectUnchanged(); 099 assertTrue("remove(present) should not remove the element", collection.contains(e0())); 100 } 101 102 @CollectionFeature.Require(absent = SUPPORTS_REMOVE) 103 public void testRemove_unsupportedNotPresent() { 104 try { 105 assertFalse( 106 "remove(notPresent) should return false or throw UnsupportedOperationException", 107 collection.remove(e3())); 108 } catch (UnsupportedOperationException tolerated) { 109 } 110 expectUnchanged(); 111 expectMissing(e3()); 112 } 113 114 @CollectionFeature.Require(value = SUPPORTS_REMOVE, absent = ALLOWS_NULL_QUERIES) 115 public void testRemove_nullNotSupported() { 116 try { 117 assertFalse( 118 "remove(null) should return false or throw NullPointerException", 119 collection.remove(null)); 120 } catch (NullPointerException tolerated) { 121 } 122 expectUnchanged(); 123 } 124 125 @CollectionFeature.Require({SUPPORTS_REMOVE, ALLOWS_NULL_QUERIES}) 126 public void testRemove_nullAllowed() { 127 assertFalse("remove(null) should return false", collection.remove(null)); 128 expectUnchanged(); 129 } 130 131 @CollectionFeature.Require(absent = SUPPORTS_REMOVE) 132 @CollectionSize.Require(absent = ZERO) 133 public void testIteratorRemove_unsupported() { 134 Iterator<E> iterator = collection.iterator(); 135 iterator.next(); 136 try { 137 iterator.remove(); 138 fail("iterator.remove() should throw UnsupportedOperationException"); 139 } catch (UnsupportedOperationException expected) { 140 } 141 expectUnchanged(); 142 assertTrue(collection.contains(e0())); 143 } 144 145 @CollectionFeature.Require(SUPPORTS_REMOVE) 146 public void testRemove_wrongType() { 147 try { 148 assertFalse(collection.remove(WrongType.VALUE)); 149 } catch (ClassCastException tolerated) { 150 } 151 expectUnchanged(); 152 } 153}