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_VALUES; 20 import static com.google.common.collect.testing.features.CollectionSize.ZERO; 21 import static com.google.common.collect.testing.features.ListFeature.SUPPORTS_SET; 22 23 import com.google.common.collect.testing.features.CollectionFeature; 24 import com.google.common.collect.testing.features.CollectionSize; 25 import com.google.common.collect.testing.features.ListFeature; 26 27 import java.lang.reflect.Method; 28 29 /** 30 * A generic JUnit test which tests {@code set()} operations on a list. Can't be 31 * invoked directly; please see 32 * {@link com.google.common.collect.testing.ListTestSuiteBuilder}. 33 * 34 * <p>This class is GWT compatible. 35 * 36 * @author George van den Driessche 37 */ 38 public class ListSetTester<E> extends AbstractListTester<E> { 39 @ListFeature.Require(SUPPORTS_SET) 40 @CollectionSize.Require(absent = ZERO) 41 public void testSet() { 42 doTestSet(samples.e3); 43 } 44 45 @CollectionSize.Require(absent = ZERO) 46 @CollectionFeature.Require(ALLOWS_NULL_VALUES) 47 @ListFeature.Require(SUPPORTS_SET) 48 public void testSet_null() { 49 doTestSet(null); 50 } 51 52 @CollectionSize.Require(absent = ZERO) 53 @CollectionFeature.Require(ALLOWS_NULL_VALUES) 54 @ListFeature.Require(SUPPORTS_SET) 55 public void testSet_replacingNull() { 56 E[] elements = createSamplesArray(); 57 int i = aValidIndex(); 58 elements[i] = null; 59 collection = getSubjectGenerator().create(elements); 60 61 doTestSet(samples.e3); 62 } 63 64 private void doTestSet(E newValue) { 65 int index = aValidIndex(); 66 E initialValue = getList().get(index); 67 assertEquals("set(i, x) should return the old element at position i.", 68 initialValue, getList().set(index, newValue)); 69 assertEquals("After set(i, x), get(i) should return x", 70 newValue, getList().get(index)); 71 assertEquals("set() should not change the size of a list.", 72 getNumElements(), getList().size()); 73 } 74 75 @ListFeature.Require(SUPPORTS_SET) 76 public void testSet_indexTooLow() { 77 try { 78 getList().set(-1, samples.e3); 79 fail("set(-1) should throw IndexOutOfBoundsException"); 80 } catch (IndexOutOfBoundsException expected) { 81 } 82 expectUnchanged(); 83 } 84 85 @ListFeature.Require(SUPPORTS_SET) 86 public void testSet_indexTooHigh() { 87 int index = getNumElements(); 88 try { 89 getList().set(index, samples.e3); 90 fail("set(size) should throw IndexOutOfBoundsException"); 91 } catch (IndexOutOfBoundsException expected) { 92 } 93 expectUnchanged(); 94 } 95 96 @CollectionSize.Require(absent = ZERO) 97 @ListFeature.Require(absent = SUPPORTS_SET) 98 public void testSet_unsupported() { 99 try { 100 getList().set(aValidIndex(), samples.e3); 101 fail("set() should throw UnsupportedOperationException"); 102 } catch (UnsupportedOperationException expected) { 103 } 104 expectUnchanged(); 105 } 106 107 @CollectionSize.Require(ZERO) 108 @ListFeature.Require(absent = SUPPORTS_SET) 109 public void testSet_unsupportedByEmptyList() { 110 try { 111 getList().set(0, samples.e3); 112 fail("set() should throw UnsupportedOperationException " 113 + "or IndexOutOfBoundsException"); 114 } catch (UnsupportedOperationException tolerated) { 115 } catch (IndexOutOfBoundsException tolerated) { 116 } 117 expectUnchanged(); 118 } 119 120 @CollectionSize.Require(absent = ZERO) 121 @ListFeature.Require(SUPPORTS_SET) 122 @CollectionFeature.Require(absent = ALLOWS_NULL_VALUES) 123 public void testSet_nullUnsupported() { 124 try { 125 getList().set(aValidIndex(), null); 126 fail("set(null) should throw NullPointerException"); 127 } catch (NullPointerException expected) { 128 } 129 expectUnchanged(); 130 } 131 132 private int aValidIndex() { 133 return getList().size() / 2; 134 } 135 136 /** 137 * Returns the {@link java.lang.reflect.Method} instance for 138 * {@link #testSet_null()} so that tests of {@link 139 * java.util.Collections#checkedCollection(java.util.Collection, Class)} can 140 * suppress it with {@code FeatureSpecificTestSuiteBuilder.suppressing()} 141 * until <a 142 * href="http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=6409434">Sun bug 143 * 6409434</a> is fixed. It's unclear whether nulls were to be permitted or 144 * forbidden, but presumably the eventual fix will be to permit them, as it 145 * seems more likely that code would depend on that behavior than on the 146 * other. Thus, we say the bug is in set(), which fails to support null. 147 */ 148 public static Method getSetNullSupportedMethod() { 149 return Platform.getMethod(ListSetTester.class, "testSet_null"); 150 } 151 } 152
