MapGenerators.java revision 1d580d0f6ee4f21eb309ba7b509d2c6d671c4044 
1/*
2 * Copyright (C) 2009 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.google;
18
19import static com.google.common.base.Preconditions.checkNotNull;
20
21import com.google.common.annotations.GwtCompatible;
22import com.google.common.collect.ImmutableMap;
23import com.google.common.collect.ImmutableMap.Builder;
24import com.google.common.collect.testing.SampleElements;
25import com.google.common.collect.testing.TestCollectionGenerator;
26import com.google.common.collect.testing.TestListGenerator;
27import com.google.common.collect.testing.TestMapEntrySetGenerator;
28import com.google.common.collect.testing.TestStringSetGenerator;
29import com.google.common.collect.testing.TestUnhashableCollectionGenerator;
30import com.google.common.collect.testing.UnhashableObject;
31
32import java.util.Collection;
33import java.util.List;
34import java.util.Map.Entry;
35import java.util.Set;
36
37/**
38 * Generators of different types of map and related collections, such as
39 * keys, entries and values.
40 *
41 * @author Hayward Chan
42 */
43@GwtCompatible
44public class MapGenerators {
45
46  public static class ImmutableMapKeySetGenerator
47      extends TestStringSetGenerator {
48    @Override protected Set<String> create(String[] elements) {
49      Builder<String, Integer> builder = ImmutableMap.builder();
50      for (String key : elements) {
51        builder.put(key, 4);
52      }
53      return builder.build().keySet();
54    }
55  }
56
57  public static class ImmutableMapValuesGenerator
58      implements TestCollectionGenerator<String> {
59
60    @Override
61    public SampleElements<String> samples() {
62      return new SampleElements.Strings();
63    }
64
65    @Override
66    public Collection<String> create(Object... elements) {
67      Builder<Object, String> builder = ImmutableMap.builder();
68      for (Object key : elements) {
69        builder.put(key, String.valueOf(key));
70      }
71      return builder.build().values();
72    }
73
74    @Override
75    public String[] createArray(int length) {
76      return new String[length];
77    }
78
79    @Override
80    public List<String> order(List<String> insertionOrder) {
81      return insertionOrder;
82    }
83  }
84
85  public static class ImmutableMapUnhashableValuesGenerator
86      extends TestUnhashableCollectionGenerator<Collection<UnhashableObject>> {
87
88    @Override public Collection<UnhashableObject> create(
89        UnhashableObject[] elements) {
90      Builder<Integer, UnhashableObject> builder = ImmutableMap.builder();
91      int key = 1;
92      for (UnhashableObject value : elements) {
93        builder.put(key++, value);
94      }
95      return builder.build().values();
96    }
97  }
98
99  public static class ImmutableMapEntrySetGenerator
100      extends TestMapEntrySetGenerator<String, String> {
101
102    public ImmutableMapEntrySetGenerator() {
103      super(new SampleElements.Strings(), new SampleElements.Strings());
104    }
105
106    @Override public Set<Entry<String, String>> createFromEntries(
107        Entry<String, String>[] entries) {
108      Builder<String, String> builder = ImmutableMap.builder();
109      for (Entry<String, String> entry : entries) {
110        // This null-check forces NPE to be thrown for tests with null
111        // elements.  Those tests aren't useful in testing entry sets
112        // because entry sets never have null elements.
113        checkNotNull(entry);
114        builder.put(entry.getKey(), entry.getValue());
115      }
116      return builder.build().entrySet();
117    }
118  }
119
120  public static class ImmutableMapValueListGenerator
121      implements TestListGenerator<String> {
122    @Override
123    public SampleElements<String> samples() {
124      return new SampleElements.Strings();
125    }
126
127    @Override
128    public List<String> create(Object... elements) {
129      Builder<Integer, String> builder = ImmutableMap.builder();
130      for (int i = 0; i < elements.length; i++) {
131        builder.put(i, toStringOrNull(elements[i]));
132      }
133      return builder.build().values().asList();
134    }
135
136    @Override
137    public String[] createArray(int length) {
138      return new String[length];
139    }
140
141    @Override
142    public Iterable<String> order(List<String> insertionOrder) {
143      return insertionOrder;
144    }
145  }
146
147  private static String toStringOrNull(Object o) {
148    return (o == null) ? null : o.toString();
149  }
150}
151