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