AbstractCollectionTester.java revision 7dd252788645e940eada959bdde927426e2531c9
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 17package com.google.common.collect.testing; 18 19import com.google.common.annotations.GwtCompatible; 20 21import java.util.Collection; 22 23/** 24 * Base class for collection testers. 25 * 26 * <p>This class is GWT compatible. 27 * 28 * @param <E> the element type of the collection to be tested. 29 * 30 * @author Kevin Bourrillion 31 */ 32@GwtCompatible 33public abstract class AbstractCollectionTester<E> 34 extends AbstractContainerTester<Collection<E>, E> { 35 36 // TODO: replace this with an accessor. 37 protected Collection<E> collection; 38 39 @Override protected Collection<E> actualContents() { 40 return collection; 41 } 42 43 // TODO: dispose of this once collection is encapsulated. 44 @Override protected Collection<E> resetContainer(Collection<E> newContents) { 45 collection = super.resetContainer(newContents); 46 return collection; 47 } 48 49 /** @see AbstractContainerTester#resetContainer() */ 50 protected void resetCollection() { 51 resetContainer(); 52 } 53 54 /** 55 * @return an array of the proper size with {@code null} inserted into the 56 * middle element. 57 */ 58 protected E[] createArrayWithNullElement() { 59 E[] array = createSamplesArray(); 60 array[getNullLocation()] = null; 61 return array; 62 } 63 64 protected void initCollectionWithNullElement() { 65 E[] array = createArrayWithNullElement(); 66 resetContainer(getSubjectGenerator().create(array)); 67 } 68 69 /** 70 * Equivalent to {@link #expectMissing(Object[]) expectMissing}{@code (null)} 71 * except that the call to {@code contains(null)} is permitted to throw a 72 * {@code NullPointerException}. 73 * 74 * @param message message to use upon assertion failure 75 */ 76 protected void expectNullMissingWhenNullUnsupported(String message) { 77 try { 78 assertFalse(message, actualContents().contains(null)); 79 } catch (NullPointerException tolerated) { 80 // Tolerated 81 } 82 } 83} 84