1 /* 2 * Copyright (C) 2007 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; 18 19 import com.google.common.annotations.GwtCompatible; 20 import com.google.errorprone.annotations.CanIgnoreReturnValue; 21 import java.util.Collection; 22 import org.checkerframework.checker.nullness.qual.Nullable; 23 import org.junit.Ignore; 24 25 /** 26 * Base class for collection testers. 27 * 28 * @param <E> the element type of the collection to be tested. 29 * @author Kevin Bourrillion 30 */ 31 @GwtCompatible 32 @Ignore // Affects only Android test runner, which respects JUnit 4 annotations on JUnit 3 tests. 33 @SuppressWarnings("JUnit4ClassUsedInJUnit3") 34 @ElementTypesAreNonnullByDefault 35 public abstract class AbstractCollectionTester<E extends @Nullable Object> 36 extends AbstractContainerTester<Collection<E>, E> { 37 38 // TODO: replace this with an accessor. 39 protected Collection<E> collection; 40 41 @Override actualContents()42 protected Collection<E> actualContents() { 43 return collection; 44 } 45 46 // TODO: dispose of this once collection is encapsulated. 47 @Override 48 @CanIgnoreReturnValue resetContainer(Collection<E> newContents)49 protected Collection<E> resetContainer(Collection<E> newContents) { 50 collection = super.resetContainer(newContents); 51 return collection; 52 } 53 54 /** @see AbstractContainerTester#resetContainer() */ resetCollection()55 protected void resetCollection() { 56 resetContainer(); 57 } 58 59 /** @return an array of the proper size with {@code null} inserted into the middle element. */ createArrayWithNullElement()60 protected E[] createArrayWithNullElement() { 61 E[] array = createSamplesArray(); 62 array[getNullLocation()] = null; 63 return array; 64 } 65 initCollectionWithNullElement()66 protected void initCollectionWithNullElement() { 67 E[] array = createArrayWithNullElement(); 68 resetContainer(getSubjectGenerator().create(array)); 69 } 70 71 /** 72 * Equivalent to {@link #expectMissing(Object[]) expectMissing}{@code (null)} except that the call 73 * to {@code contains(null)} is permitted to throw a {@code NullPointerException}. 74 * 75 * @param message message to use upon assertion failure 76 */ expectNullMissingWhenNullUnsupported(String message)77 protected void expectNullMissingWhenNullUnsupported(String message) { 78 try { 79 assertFalse(message, actualContents().contains(null)); 80 } catch (NullPointerException tolerated) { 81 // Tolerated 82 } 83 } 84 } 85