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