SortedMapNavigationTester.java revision 3c77433663281544363151bf284b0240dfd22a42 
1/*
2 * Copyright (C) 2010 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.CollectionSize.ONE;
20import static com.google.common.collect.testing.features.CollectionSize.SEVERAL;
21import static com.google.common.collect.testing.features.CollectionSize.ZERO;
22
23import com.google.common.annotations.GwtCompatible;
24import com.google.common.collect.testing.AbstractMapTester;
25import com.google.common.collect.testing.Helpers;
26import com.google.common.collect.testing.features.CollectionSize;
27
28import java.util.Collections;
29import java.util.List;
30import java.util.Map.Entry;
31import java.util.NoSuchElementException;
32import java.util.SortedMap;
33
34/**
35 * A generic JUnit test which tests operations on a SortedMap. Can't be
36 * invoked directly; please see {@code SortedMapTestSuiteBuilder}.
37 *
38 * @author Jesse Wilson
39 * @author Louis Wasserman
40 */
41@GwtCompatible
42public class SortedMapNavigationTester<K, V> extends AbstractMapTester<K, V> {
43
44  private SortedMap<K, V> navigableMap;
45  private Entry<K, V> a;
46  private Entry<K, V> c;
47
48  @Override public void setUp() throws Exception {
49    super.setUp();
50    navigableMap = (SortedMap<K, V>) getMap();
51    List<Entry<K, V>> entries = Helpers.copyToList(getSubjectGenerator().getSampleElements(
52        getSubjectGenerator().getCollectionSize().getNumElements()));
53    Collections.sort(entries, Helpers.<K, V>entryComparator(navigableMap.comparator()));
54
55    // some tests assume SEVERAL == 3
56    if (entries.size() >= 1) {
57      a = entries.get(0);
58      if (entries.size() >= 3) {
59        c = entries.get(2);
60      }
61    }
62  }
63
64  @CollectionSize.Require(ZERO)
65  public void testEmptyMapFirst() {
66    try {
67      navigableMap.firstKey();
68      fail();
69    } catch (NoSuchElementException e) {
70    }
71  }
72
73  @CollectionSize.Require(ZERO)
74  public void testEmptyMapLast() {
75    try {
76      assertNull(navigableMap.lastKey());
77      fail();
78    } catch (NoSuchElementException e) {
79    }
80  }
81
82  @CollectionSize.Require(ONE)
83  public void testSingletonMapFirst() {
84    assertEquals(a.getKey(), navigableMap.firstKey());
85  }
86
87  @CollectionSize.Require(ONE)
88  public void testSingletonMapLast() {
89    assertEquals(a.getKey(), navigableMap.lastKey());
90  }
91
92  @CollectionSize.Require(SEVERAL)
93  public void testFirst() {
94    assertEquals(a.getKey(), navigableMap.firstKey());
95  }
96
97  @CollectionSize.Require(SEVERAL)
98  public void testLast() {
99    assertEquals(c.getKey(), navigableMap.lastKey());
100  }
101}
102