1 /*
2  * Copyright (C) 2016 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 
17 package com.google.common.graph;
18 
19 import static com.google.common.truth.Truth.assertThat;
20 
21 import com.google.common.collect.Ordering;
22 import java.util.Arrays;
23 import java.util.Collection;
24 import java.util.Comparator;
25 import java.util.HashMap;
26 import java.util.TreeMap;
27 import org.junit.Before;
28 import org.junit.Test;
29 import org.junit.runner.RunWith;
30 import org.junit.runners.Parameterized;
31 import org.junit.runners.Parameterized.Parameters;
32 
33 /** Tests for {@link MapIteratorCache} and {@link MapRetrievalCache}. */
34 @AndroidIncompatible
35 // TODO(cpovirk): Figure out Android JUnit 4 support. Does it work with Gingerbread? @RunWith?
36 @RunWith(Parameterized.class)
37 public final class MapCacheTest {
38   private final MapIteratorCache<String, String> mapCache;
39 
MapCacheTest(MapIteratorCache<String, String> mapCache)40   public MapCacheTest(MapIteratorCache<String, String> mapCache) {
41     this.mapCache = mapCache;
42   }
43 
44   @Parameters
parameters()45   public static Collection<Object[]> parameters() {
46     Comparator<String> nullsLast = Ordering.natural().nullsLast();
47 
48     return Arrays.asList(
49         new Object[][] {
50           {new MapIteratorCache<String, String>(new HashMap<String, String>())},
51           {new MapIteratorCache<String, String>(new TreeMap<String, String>(nullsLast))},
52           {new MapRetrievalCache<String, String>(new HashMap<String, String>())},
53           {new MapRetrievalCache<String, String>(new TreeMap<String, String>(nullsLast))}
54         });
55   }
56 
57   @Before
init()58   public void init() {
59     mapCache.clear();
60   }
61 
62   @Test
testKeySetIterator()63   public void testKeySetIterator() {
64     mapCache.put("A", "A_value");
65     mapCache.put("B", "B_value");
66     mapCache.put("C", "C_value");
67 
68     assertThat(mapCache.unmodifiableKeySet()).hasSize(3);
69     for (String key : mapCache.unmodifiableKeySet()) {
70       assertThat(mapCache.get(key)).isEqualTo(key + "_value");
71     }
72   }
73 
74   @Test
testPutNewValue()75   public void testPutNewValue() {
76     assertThat(mapCache.put("key", "value")).isNull();
77     assertThat(mapCache.get("key")).isEqualTo("value"); // ensure key/value is cached
78     assertThat(mapCache.put("key", "new value")).isEqualTo("value");
79     assertThat(mapCache.get("key")).isEqualTo("new value");
80   }
81 
82   @Test
testRemoveEqualKeyWithDifferentReference()83   public void testRemoveEqualKeyWithDifferentReference() {
84     String fooReference1 = new String("foo");
85     String fooReference2 = new String("foo");
86     assertThat(fooReference1).isNotSameInstanceAs(fooReference2);
87 
88     assertThat(mapCache.put(fooReference1, "bar")).isNull();
89     assertThat(mapCache.get(fooReference1)).isEqualTo("bar"); // ensure first reference is cached
90     assertThat(mapCache.remove(fooReference2)).isEqualTo("bar");
91     assertThat(mapCache.get(fooReference1)).isNull();
92   }
93 
94   @Test
testHandleNulls()95   public void testHandleNulls() {
96     mapCache.put("foo", "bar");
97     mapCache.put("non-null key", null);
98     mapCache.put(null, "non-null value");
99 
100     assertThat(mapCache.get("foo")).isEqualTo("bar");
101     assertThat(mapCache.get("non-null key")).isNull();
102     assertThat(mapCache.get(null)).isEqualTo("non-null value");
103 
104     assertThat(mapCache.containsKey("foo")).isTrue();
105     assertThat(mapCache.containsKey("bar")).isFalse();
106     assertThat(mapCache.containsKey("non-null key")).isTrue();
107     assertThat(mapCache.containsKey(null)).isTrue();
108 
109     // Test again - in reverse order.
110     assertThat(mapCache.get(null)).isEqualTo("non-null value");
111     assertThat(mapCache.get("non-null key")).isNull();
112     assertThat(mapCache.get("foo")).isEqualTo("bar");
113   }
114 }
115