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.Helpers.getMethod; 020import static com.google.common.collect.testing.features.CollectionFeature.ALLOWS_NULL_VALUES; 021import static com.google.common.collect.testing.features.CollectionSize.ZERO; 022import static com.google.common.collect.testing.features.ListFeature.SUPPORTS_SET; 023import static com.google.common.collect.testing.testers.ReflectionFreeAssertThrows.assertThrows; 024 025import com.google.common.annotations.GwtCompatible; 026import com.google.common.annotations.GwtIncompatible; 027import com.google.common.annotations.J2ktIncompatible; 028import com.google.common.collect.testing.features.CollectionFeature; 029import com.google.common.collect.testing.features.CollectionSize; 030import com.google.common.collect.testing.features.ListFeature; 031import java.lang.reflect.Method; 032import org.junit.Ignore; 033 034/** 035 * A generic JUnit test which tests {@code set()} operations on a list. Can't be invoked directly; 036 * please see {@link com.google.common.collect.testing.ListTestSuiteBuilder}. 037 * 038 * @author George van den Driessche 039 */ 040@GwtCompatible(emulated = true) 041@Ignore("test runners must not instantiate and run this directly, only via suites we build") 042// @Ignore affects the Android test runner, which respects JUnit 4 annotations on JUnit 3 tests. 043@SuppressWarnings("JUnit4ClassUsedInJUnit3") 044public class ListSetTester<E> extends AbstractListTester<E> { 045 @ListFeature.Require(SUPPORTS_SET) 046 @CollectionSize.Require(absent = ZERO) 047 public void testSet() { 048 doTestSet(e3()); 049 } 050 051 @CollectionSize.Require(absent = ZERO) 052 @CollectionFeature.Require(ALLOWS_NULL_VALUES) 053 @ListFeature.Require(SUPPORTS_SET) 054 public void testSet_null() { 055 doTestSet(null); 056 } 057 058 @CollectionSize.Require(absent = ZERO) 059 @CollectionFeature.Require(ALLOWS_NULL_VALUES) 060 @ListFeature.Require(SUPPORTS_SET) 061 public void testSet_replacingNull() { 062 E[] elements = createSamplesArray(); 063 int i = aValidIndex(); 064 elements[i] = null; 065 collection = getSubjectGenerator().create(elements); 066 067 doTestSet(e3()); 068 } 069 070 private void doTestSet(E newValue) { 071 int index = aValidIndex(); 072 E initialValue = getList().get(index); 073 assertEquals( 074 "set(i, x) should return the old element at position i.", 075 initialValue, 076 getList().set(index, newValue)); 077 assertEquals("After set(i, x), get(i) should return x", newValue, getList().get(index)); 078 assertEquals("set() should not change the size of a list.", getNumElements(), getList().size()); 079 } 080 081 @ListFeature.Require(SUPPORTS_SET) 082 public void testSet_indexTooLow() { 083 assertThrows(IndexOutOfBoundsException.class, () -> getList().set(-1, e3())); 084 expectUnchanged(); 085 } 086 087 @ListFeature.Require(SUPPORTS_SET) 088 public void testSet_indexTooHigh() { 089 int index = getNumElements(); 090 assertThrows(IndexOutOfBoundsException.class, () -> getList().set(index, e3())); 091 expectUnchanged(); 092 } 093 094 @CollectionSize.Require(absent = ZERO) 095 @ListFeature.Require(absent = SUPPORTS_SET) 096 public void testSet_unsupported() { 097 assertThrows(UnsupportedOperationException.class, () -> getList().set(aValidIndex(), e3())); 098 expectUnchanged(); 099 } 100 101 @CollectionSize.Require(ZERO) 102 @ListFeature.Require(absent = SUPPORTS_SET) 103 public void testSet_unsupportedByEmptyList() { 104 try { 105 getList().set(0, e3()); 106 fail("set() should throw UnsupportedOperationException or IndexOutOfBoundsException"); 107 } catch (UnsupportedOperationException | IndexOutOfBoundsException expected) { 108 } 109 expectUnchanged(); 110 } 111 112 @CollectionSize.Require(absent = ZERO) 113 @ListFeature.Require(SUPPORTS_SET) 114 @CollectionFeature.Require(absent = ALLOWS_NULL_VALUES) 115 public void testSet_nullUnsupported() { 116 assertThrows(NullPointerException.class, () -> getList().set(aValidIndex(), null)); 117 expectUnchanged(); 118 } 119 120 private int aValidIndex() { 121 return getList().size() / 2; 122 } 123 124 /** 125 * Returns the {@link java.lang.reflect.Method} instance for {@link #testSet_null()} so that tests 126 * of {@link java.util.Collections#checkedCollection(java.util.Collection, Class)} can suppress it 127 * with {@code FeatureSpecificTestSuiteBuilder.suppressing()} until <a 128 * href="https://bugs.openjdk.org/browse/JDK-6409434">JDK-6409434</a> is fixed. It's unclear 129 * whether nulls were to be permitted or forbidden, but presumably the eventual fix will be to 130 * permit them, as it seems more likely that code would depend on that behavior than on the other. 131 * Thus, we say the bug is in set(), which fails to support null. 132 */ 133 @J2ktIncompatible 134 @GwtIncompatible // reflection 135 public static Method getSetNullSupportedMethod() { 136 return getMethod(ListSetTester.class, "testSet_null"); 137 } 138}