QueueOfferTester.java revision 3c77433663281544363151bf284b0240dfd22a42 
1/*
2 * Copyright (C) 2008 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.testers;
18
19import static com.google.common.collect.testing.features.CollectionFeature.ALLOWS_NULL_VALUES;
20import static com.google.common.collect.testing.features.CollectionFeature.SUPPORTS_ADD;
21
22import com.google.common.annotations.GwtCompatible;
23import com.google.common.collect.testing.features.CollectionFeature;
24
25/**
26 * A generic JUnit test which tests offer operations on a queue. Can't be
27 * invoked directly; please see
28 * {@link com.google.common.collect.testing.CollectionTestSuiteBuilder}.
29 *
30 * <p>This class is GWT compatible.
31 *
32 * @author Jared Levy
33 */
34@SuppressWarnings("unchecked") // too many "unchecked generic array creations"
35@GwtCompatible
36public class QueueOfferTester<E> extends AbstractQueueTester<E> {
37  @CollectionFeature.Require(SUPPORTS_ADD)
38  public void testOffer_supportedNotPresent() {
39    assertTrue("offer(notPresent) should return true",
40        getQueue().offer(samples.e3));
41    expectAdded(samples.e3);
42  }
43
44  @CollectionFeature.Require({SUPPORTS_ADD, ALLOWS_NULL_VALUES})
45  public void testOffer_nullSupported() {
46    assertTrue("offer(null) should return true", getQueue().offer(null));
47    expectAdded((E) null);
48  }
49
50  @CollectionFeature.Require(value = SUPPORTS_ADD, absent = ALLOWS_NULL_VALUES)
51  public void testOffer_nullUnsupported() {
52    try {
53      getQueue().offer(null);
54      fail("offer(null) should throw");
55    } catch (NullPointerException expected) {
56    }
57    expectUnchanged();
58    expectNullMissingWhenNullUnsupported(
59        "Should not contain null after unsupported offer(null)");
60  }
61}
62