| /* |
| * Copyright (C) 2008 The Guava Authors |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package com.google.common.collect.testing.testers; |
| |
| import static com.google.common.collect.testing.features.CollectionFeature.ALLOWS_NULL_VALUES; |
| |
| import com.google.common.annotations.GwtCompatible; |
| import com.google.common.annotations.GwtIncompatible; |
| import com.google.common.collect.testing.Helpers; |
| import com.google.common.collect.testing.features.CollectionFeature; |
| import com.google.common.collect.testing.features.CollectionSize; |
| import java.lang.reflect.Method; |
| import java.util.Collection; |
| import org.junit.Ignore; |
| |
| /** |
| * Tests {@link java.util.Set#hashCode}. |
| * |
| * @author George van den Driessche |
| */ |
| @GwtCompatible(emulated = true) |
| @Ignore // Affects only Android test runner, which respects JUnit 4 annotations on JUnit 3 tests. |
| public class SetHashCodeTester<E> extends AbstractSetTester<E> { |
| public void testHashCode() { |
| int expectedHashCode = 0; |
| for (E element : getSampleElements()) { |
| expectedHashCode += ((element == null) ? 0 : element.hashCode()); |
| } |
| assertEquals( |
| "A Set's hashCode() should be the sum of those of its elements.", |
| expectedHashCode, |
| getSet().hashCode()); |
| } |
| |
| @CollectionSize.Require(absent = CollectionSize.ZERO) |
| @CollectionFeature.Require(ALLOWS_NULL_VALUES) |
| public void testHashCode_containingNull() { |
| Collection<E> elements = getSampleElements(getNumElements() - 1); |
| int expectedHashCode = 0; |
| for (E element : elements) { |
| expectedHashCode += ((element == null) ? 0 : element.hashCode()); |
| } |
| |
| elements.add(null); |
| collection = getSubjectGenerator().create(elements.toArray()); |
| assertEquals( |
| "A Set's hashCode() should be the sum of those of its elements (with " |
| + "a null element counting as having a hash of zero).", |
| expectedHashCode, |
| getSet().hashCode()); |
| } |
| |
| /** |
| * Returns the {@link Method} instances for the test methods in this class which call {@code |
| * hashCode()} on the set values so that set tests on unhashable objects can suppress it with |
| * {@code FeatureSpecificTestSuiteBuilder.suppressing()}. |
| */ |
| @GwtIncompatible // reflection |
| public static Method[] getHashCodeMethods() { |
| return new Method[] { |
| Helpers.getMethod(SetHashCodeTester.class, "testHashCode"), |
| Helpers.getMethod(SetHashCodeTester.class, "testHashCode_containingNull") |
| }; |
| } |
| } |