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.features.CollectionFeature.ALLOWS_NULL_VALUES;
020import static com.google.common.collect.testing.features.CollectionFeature.SUPPORTS_ADD;
021import static org.junit.Assert.assertThrows;
022
023import com.google.common.annotations.GwtCompatible;
024import com.google.common.collect.testing.features.CollectionFeature;
025
026/**
027 * A generic JUnit test which tests offer operations on a queue. Can't be invoked directly; please
028 * see {@link com.google.common.collect.testing.CollectionTestSuiteBuilder}.
029 *
030 * @author Jared Levy
031 */
032@GwtCompatible
033public class QueueOfferTester<E> extends AbstractQueueTester<E> {
034  @CollectionFeature.Require(SUPPORTS_ADD)
035  public void testOffer_supportedNotPresent() {
036    assertTrue("offer(notPresent) should return true", getQueue().offer(e3()));
037    expectAdded(e3());
038  }
039
040  @CollectionFeature.Require({SUPPORTS_ADD, ALLOWS_NULL_VALUES})
041  public void testOffer_nullSupported() {
042    assertTrue("offer(null) should return true", getQueue().offer(null));
043    expectAdded((E) null);
044  }
045
046  @CollectionFeature.Require(value = SUPPORTS_ADD, absent = ALLOWS_NULL_VALUES)
047  public void testOffer_nullUnsupported() {
048    assertThrows(NullPointerException.class, () -> getQueue().offer(null));
049    expectUnchanged();
050    expectNullMissingWhenNullUnsupported("Should not contain null after unsupported offer(null)");
051  }
052}