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;
18
19import static java.util.Arrays.asList;
20
21import com.google.common.annotations.GwtIncompatible;
22import com.google.common.base.Objects;
23import com.google.common.base.Predicate;
24import com.google.common.base.Predicates;
25import com.google.common.collect.testing.features.CollectionFeature;
26import com.google.common.collect.testing.features.CollectionSize;
27import com.google.common.collect.testing.google.MultisetTestSuiteBuilder;
28import com.google.common.collect.testing.google.SortedMultisetTestSuiteBuilder;
29import com.google.common.collect.testing.google.TestStringMultisetGenerator;
30
31import junit.framework.Test;
32import junit.framework.TestCase;
33import junit.framework.TestSuite;
34
35import java.util.ArrayList;
36import java.util.Collections;
37import java.util.List;
38
39/**
40 * Collection tests on wrappers from {@link Multisets}.
41 *
42 * @author Jared Levy
43 */
44@GwtIncompatible("suite") // TODO(cpovirk): set up collect/gwt/suites version
45public class MultisetsCollectionTest extends TestCase {
46  public static Test suite() {
47    TestSuite suite = new TestSuite();
48
49    suite.addTest(MultisetTestSuiteBuilder.using(
50        unmodifiableMultisetGenerator())
51        .withFeatures(CollectionSize.ANY, CollectionFeature.KNOWN_ORDER,
52            CollectionFeature.SERIALIZABLE,
53            CollectionFeature.ALLOWS_NULL_QUERIES)
54        .named("Multisets.unmodifiableMultiset[LinkedHashMultiset]")
55        .createTestSuite());
56
57    suite.addTest(SortedMultisetTestSuiteBuilder.using(unmodifiableSortedMultisetGenerator())
58        .withFeatures(CollectionSize.ANY, CollectionFeature.KNOWN_ORDER,
59            CollectionFeature.ALLOWS_NULL_QUERIES)
60        .named("Multisets.unmodifiableMultiset[TreeMultiset]")
61        .createTestSuite());
62
63    suite.addTest(MultisetTestSuiteBuilder.using(unionGenerator())
64        .withFeatures(CollectionSize.ANY,
65            CollectionFeature.ALLOWS_NULL_VALUES)
66        .named("Multisets.union")
67        .createTestSuite());
68
69    suite.addTest(MultisetTestSuiteBuilder.using(intersectionGenerator())
70        .withFeatures(CollectionSize.ANY,
71            CollectionFeature.ALLOWS_NULL_VALUES,
72            CollectionFeature.KNOWN_ORDER)
73        .named("Multisets.intersection")
74        .createTestSuite());
75
76    suite.addTest(MultisetTestSuiteBuilder.using(sumGenerator())
77        .withFeatures(CollectionSize.ANY,
78            CollectionFeature.ALLOWS_NULL_VALUES)
79        .named("Multisets.sum")
80        .createTestSuite());
81
82    suite.addTest(MultisetTestSuiteBuilder.using(differenceGenerator())
83        .withFeatures(CollectionSize.ANY,
84            CollectionFeature.ALLOWS_NULL_VALUES,
85            CollectionFeature.KNOWN_ORDER)
86        .named("Multisets.difference")
87        .createTestSuite());
88
89    suite.addTest(MultisetTestSuiteBuilder.using(filteredGenerator())
90        .withFeatures(CollectionSize.ANY,
91            CollectionFeature.ALLOWS_NULL_VALUES,
92            CollectionFeature.KNOWN_ORDER,
93            CollectionFeature.SUPPORTS_ADD,
94            CollectionFeature.SUPPORTS_REMOVE)
95        .named("Multiset.filter[Multiset, Predicate]")
96        .createTestSuite());
97
98    return suite;
99  }
100
101  private static TestStringMultisetGenerator unmodifiableMultisetGenerator() {
102    return new TestStringMultisetGenerator() {
103      @Override protected Multiset<String> create(String[] elements) {
104        return Multisets.unmodifiableMultiset(
105            LinkedHashMultiset.create(asList(elements)));
106      }
107      @Override public List<String> order(List<String> insertionOrder) {
108        List<String> order = new ArrayList<String>();
109        for (String s : insertionOrder) {
110          int index = order.indexOf(s);
111          if (index == -1) {
112            order.add(s);
113          } else {
114            order.add(index, s);
115          }
116        }
117        return order;
118      }
119    };
120  }
121
122  private static TestStringMultisetGenerator unmodifiableSortedMultisetGenerator() {
123    return new TestStringMultisetGenerator() {
124      @Override protected Multiset<String> create(String[] elements) {
125        return Multisets.unmodifiableSortedMultiset(
126            TreeMultiset.create(asList(elements)));
127      }
128      @Override public List<String> order(List<String> insertionOrder) {
129        Collections.sort(insertionOrder);
130        return insertionOrder;
131      }
132    };
133  }
134
135  private static TestStringMultisetGenerator unionGenerator() {
136    return new TestStringMultisetGenerator() {
137      @Override
138      protected Multiset<String> create(String[] elements) {
139        Multiset<String> multiset1 = LinkedHashMultiset.create();
140        Multiset<String> multiset2 = LinkedHashMultiset.create();
141        for (int i = 0; i < elements.length; i++) {
142          String element = elements[i];
143          if (multiset1.contains(element) ||
144              multiset2.contains(element)) {
145            // add to both; the one already containing it will have more
146            multiset1.add(element);
147            multiset2.add(element);
148          } else if (i % 2 == 0) {
149            multiset1.add(elements[i]);
150          } else {
151            multiset2.add(elements[i]);
152          }
153        }
154        return Multisets.union(multiset1, multiset2);
155      }
156    };
157  }
158
159  private static TestStringMultisetGenerator intersectionGenerator() {
160    return new TestStringMultisetGenerator() {
161      @Override protected Multiset<String> create(String[] elements) {
162        Multiset<String> multiset1 = LinkedHashMultiset.create();
163        Multiset<String> multiset2 = LinkedHashMultiset.create();
164        multiset1.add("only1");
165        multiset2.add("only2");
166        for (int i = 0; i < elements.length; i++) {
167          multiset1.add(elements[i]);
168          multiset2.add(elements[elements.length - 1 - i]);
169        }
170        if (elements.length > 0) {
171          multiset1.add(elements[0]);
172        }
173        if (elements.length > 1) {
174          /*
175           * When a test requests a multiset with duplicates, our plan of
176           * "add an extra item 0 to A and an extra item 1 to B" really means
177           * "add an extra item 0 to A and B," which isn't what we want.
178           */
179          if (!Objects.equal(elements[0], elements[1])) {
180            multiset2.add(elements[1], 2);
181          }
182        }
183        return Multisets.intersection(multiset1, multiset2);
184      }
185    };
186  }
187
188  private static TestStringMultisetGenerator sumGenerator() {
189    return new TestStringMultisetGenerator() {
190      @Override protected Multiset<String> create(String[] elements) {
191        Multiset<String> multiset1 = LinkedHashMultiset.create();
192        Multiset<String> multiset2 = LinkedHashMultiset.create();
193        for (int i = 0; i < elements.length; i++) {
194          // add to either; sum should contain all
195          if (i % 2 == 0) {
196            multiset1.add(elements[i]);
197          } else {
198            multiset2.add(elements[i]);
199          }
200        }
201        return Multisets.sum(multiset1, multiset2);
202      }
203    };
204  }
205
206  private static TestStringMultisetGenerator differenceGenerator() {
207    return new TestStringMultisetGenerator() {
208      @Override protected Multiset<String> create(String[] elements) {
209        Multiset<String> multiset1 = LinkedHashMultiset.create();
210        Multiset<String> multiset2 = LinkedHashMultiset.create();
211        multiset1.add("equalIn1");
212        multiset1.add("fewerIn1");
213        multiset2.add("equalIn1");
214        multiset2.add("fewerIn1", 3);
215        multiset2.add("onlyIn2", 2);
216        for (int i = 0; i < elements.length; i++) {
217          // add 1 more copy of each element to multiset1 than multiset2
218          multiset1.add(elements[i], i + 2);
219          multiset2.add(elements[i], i + 1);
220        }
221        return Multisets.difference(multiset1, multiset2);
222      }
223    };
224  }
225
226  private static final Multiset<String> ELEMENTS_TO_FILTER_OUT = ImmutableMultiset.of(
227      "foobar", "bazfoo", "foobar", "foobar");
228
229  private static final Predicate<String> PREDICATE =
230      Predicates.not(Predicates.in(ELEMENTS_TO_FILTER_OUT));
231
232  private static TestStringMultisetGenerator filteredGenerator() {
233    return new TestStringMultisetGenerator() {
234      @Override
235      protected Multiset<String> create(String[] elements) {
236        Multiset<String> multiset = LinkedHashMultiset.create();
237        Collections.addAll(multiset, elements);
238        multiset.addAll(ELEMENTS_TO_FILTER_OUT);
239        return Multisets.filter(multiset, PREDICATE);
240      }
241
242      @Override
243      public List<String> order(List<String> insertionOrder) {
244        return Lists.newArrayList(LinkedHashMultiset.create(insertionOrder));
245      }
246    };
247  }
248}
249