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.KNOWN_ORDER;
020import static com.google.common.collect.testing.features.CollectionFeature.SUPPORTS_REMOVE;
021import static com.google.common.collect.testing.features.CollectionSize.ONE;
022import static com.google.common.collect.testing.features.CollectionSize.SEVERAL;
023import static com.google.common.collect.testing.features.CollectionSize.ZERO;
024
025import com.google.common.annotations.GwtCompatible;
026import com.google.common.collect.testing.features.CollectionFeature;
027import com.google.common.collect.testing.features.CollectionSize;
028
029/**
030 * A generic JUnit test which tests {@code poll()} operations on a queue. Can't be invoked directly;
031 * please see {@link com.google.common.collect.testing.CollectionTestSuiteBuilder}.
032 *
033 * @author Jared Levy
034 */
035@GwtCompatible
036public class QueuePollTester<E> extends AbstractQueueTester<E> {
037  @CollectionFeature.Require(SUPPORTS_REMOVE)
038  @CollectionSize.Require(ZERO)
039  public void testPoll_empty() {
040    assertNull("emptyQueue.poll() should return null", getQueue().poll());
041    expectUnchanged();
042  }
043
044  @CollectionFeature.Require(SUPPORTS_REMOVE)
045  @CollectionSize.Require(ONE)
046  public void testPoll_size1() {
047    assertEquals("size1Queue.poll() should return first element", e0(), getQueue().poll());
048    expectMissing(e0());
049  }
050
051  @CollectionFeature.Require({KNOWN_ORDER, SUPPORTS_REMOVE})
052  @CollectionSize.Require(SEVERAL)
053  public void testPoll_sizeMany() {
054    assertEquals("sizeManyQueue.poll() should return first element", e0(), getQueue().poll());
055    expectMissing(e0());
056  }
057}