1/*
2 * Copyright (C) 2011 The Guava Authors
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
5 * in compliance with the License. You may obtain a copy of the License at
6 *
7 * http://www.apache.org/licenses/LICENSE-2.0
8 *
9 * Unless required by applicable law or agreed to in writing, software distributed under the License
10 * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
11 * or implied. See the License for the specific language governing permissions and limitations under
12 * the License.
13 */
14
15package com.google.common.cache;
16
17import static com.google.common.cache.CacheTesting.checkEmpty;
18import static com.google.common.cache.CacheTesting.checkValidState;
19import static com.google.common.cache.TestingCacheLoaders.identityLoader;
20import static com.google.common.truth.Truth.assertThat;
21import static java.util.concurrent.TimeUnit.DAYS;
22import static java.util.concurrent.TimeUnit.SECONDS;
23
24import com.google.common.base.Function;
25import com.google.common.cache.CacheBuilderFactory.DurationSpec;
26import com.google.common.cache.LocalCache.Strength;
27import com.google.common.collect.ImmutableMap;
28import com.google.common.collect.ImmutableSet;
29import com.google.common.collect.Iterables;
30import com.google.common.collect.Iterators;
31import com.google.common.collect.Lists;
32import com.google.common.collect.Maps;
33import com.google.common.testing.EqualsTester;
34
35import junit.framework.TestCase;
36
37import java.util.Collection;
38import java.util.List;
39import java.util.Map;
40import java.util.Map.Entry;
41import java.util.Set;
42
43/**
44 * {@link LoadingCache} tests that deal with caches that actually contain some key-value mappings.
45 *
46 * @author mike nonemacher
47 */
48
49public class PopulatedCachesTest extends TestCase {
50  // we use integers as keys; make sure the range covers some values that ARE cached by
51  // Integer.valueOf(int), and some that are not cached. (127 is the highest cached value.)
52  static final int WARMUP_MIN = 120;
53  static final int WARMUP_MAX = 135;
54  static final int WARMUP_SIZE = WARMUP_MAX - WARMUP_MIN;
55
56  public void testSize_populated() {
57    for (LoadingCache<Object, Object> cache : caches()) {
58      // don't let the entries get GCed
59      List<Entry<Object, Object>> warmed = warmUp(cache);
60      assertEquals(WARMUP_SIZE, cache.size());
61      assertMapSize(cache.asMap(), WARMUP_SIZE);
62      checkValidState(cache);
63    }
64  }
65
66  public void testContainsKey_found() {
67    for (LoadingCache<Object, Object> cache : caches()) {
68      // don't let the entries get GCed
69      List<Entry<Object, Object>> warmed = warmUp(cache);
70      for (int i = WARMUP_MIN; i < WARMUP_MAX; i++) {
71        Entry<Object, Object> entry = warmed.get(i - WARMUP_MIN);
72        assertTrue(cache.asMap().containsKey(entry.getKey()));
73        assertTrue(cache.asMap().containsValue(entry.getValue()));
74        // this getUnchecked() call shouldn't be a cache miss; verified below
75        assertEquals(entry.getValue(), cache.getUnchecked(entry.getKey()));
76      }
77      assertEquals(WARMUP_SIZE, cache.stats().missCount());
78      checkValidState(cache);
79    }
80  }
81
82  public void testPut_populated() {
83    for (LoadingCache<Object, Object> cache : caches()) {
84      // don't let the entries get GCed
85      List<Entry<Object, Object>> warmed = warmUp(cache);
86      for (int i = WARMUP_MIN; i < WARMUP_MAX; i++) {
87        Entry<Object, Object> entry = warmed.get(i - WARMUP_MIN);
88        Object newValue = new Object();
89        assertSame(entry.getValue(), cache.asMap().put(entry.getKey(), newValue));
90        // don't let the new entry get GCed
91        warmed.add(entryOf(entry.getKey(), newValue));
92        Object newKey = new Object();
93        assertNull(cache.asMap().put(newKey, entry.getValue()));
94        // this getUnchecked() call shouldn't be a cache miss; verified below
95        assertEquals(newValue, cache.getUnchecked(entry.getKey()));
96        assertEquals(entry.getValue(), cache.getUnchecked(newKey));
97        // don't let the new entry get GCed
98        warmed.add(entryOf(newKey, entry.getValue()));
99      }
100      assertEquals(WARMUP_SIZE, cache.stats().missCount());
101      checkValidState(cache);
102    }
103  }
104
105  public void testPutIfAbsent_populated() {
106    for (LoadingCache<Object, Object> cache : caches()) {
107      // don't let the entries get GCed
108      List<Entry<Object, Object>> warmed = warmUp(cache);
109      for (int i = WARMUP_MIN; i < WARMUP_MAX; i++) {
110        Entry<Object, Object> entry = warmed.get(i - WARMUP_MIN);
111        Object newValue = new Object();
112        assertSame(entry.getValue(), cache.asMap().putIfAbsent(entry.getKey(), newValue));
113        Object newKey = new Object();
114        assertNull(cache.asMap().putIfAbsent(newKey, entry.getValue()));
115        // this getUnchecked() call shouldn't be a cache miss; verified below
116        assertEquals(entry.getValue(), cache.getUnchecked(entry.getKey()));
117        assertEquals(entry.getValue(), cache.getUnchecked(newKey));
118        // don't let the new entry get GCed
119        warmed.add(entryOf(newKey, entry.getValue()));
120      }
121      assertEquals(WARMUP_SIZE, cache.stats().missCount());
122      checkValidState(cache);
123    }
124  }
125
126  public void testPutAll_populated() {
127    for (LoadingCache<Object, Object> cache : caches()) {
128      // don't let the entries get GCed
129      List<Entry<Object, Object>> warmed = warmUp(cache);
130      Object newKey = new Object();
131      Object newValue = new Object();
132      cache.asMap().putAll(ImmutableMap.of(newKey, newValue));
133      // this getUnchecked() call shouldn't be a cache miss; verified below
134      assertEquals(newValue, cache.getUnchecked(newKey));
135      assertEquals(WARMUP_SIZE, cache.stats().missCount());
136      checkValidState(cache);
137    }
138  }
139
140  public void testReplace_populated() {
141    for (LoadingCache<Object, Object> cache : caches()) {
142      // don't let the entries get GCed
143      List<Entry<Object, Object>> warmed = warmUp(cache);
144      for (int i = WARMUP_MIN; i < WARMUP_MAX; i++) {
145        Entry<Object, Object> entry = warmed.get(i - WARMUP_MIN);
146        Object newValue = new Object();
147        assertSame(entry.getValue(), cache.asMap().replace(entry.getKey(), newValue));
148        assertTrue(cache.asMap().replace(entry.getKey(), newValue, entry.getValue()));
149        Object newKey = new Object();
150        assertNull(cache.asMap().replace(newKey, entry.getValue()));
151        assertFalse(cache.asMap().replace(newKey, entry.getValue(), newValue));
152        // this getUnchecked() call shouldn't be a cache miss; verified below
153        assertEquals(entry.getValue(), cache.getUnchecked(entry.getKey()));
154        assertFalse(cache.asMap().containsKey(newKey));
155      }
156      assertEquals(WARMUP_SIZE, cache.stats().missCount());
157      checkValidState(cache);
158    }
159  }
160
161  public void testRemove_byKey() {
162    for (LoadingCache<Object, Object> cache : caches()) {
163      // don't let the entries get GCed
164      List<Entry<Object, Object>> warmed = warmUp(cache);
165      for (int i = WARMUP_MIN; i < WARMUP_MAX; i++) {
166        Entry<Object, Object> entry = warmed.get(i - WARMUP_MIN);
167        Object key = entry.getKey();
168        assertEquals(entry.getValue(), cache.asMap().remove(key));
169        assertNull(cache.asMap().remove(key));
170        assertFalse(cache.asMap().containsKey(key));
171      }
172      checkEmpty(cache);
173    }
174  }
175
176  public void testRemove_byKeyAndValue() {
177    for (LoadingCache<Object, Object> cache : caches()) {
178      // don't let the entries get GCed
179      List<Entry<Object, Object>> warmed = warmUp(cache);
180      for (int i = WARMUP_MIN; i < WARMUP_MAX; i++) {
181        Object key = warmed.get(i - WARMUP_MIN).getKey();
182        Object value = warmed.get(i - WARMUP_MIN).getValue();
183        assertFalse(cache.asMap().remove(key, -1));
184        assertTrue(cache.asMap().remove(key, value));
185        assertFalse(cache.asMap().remove(key, -1));
186        assertFalse(cache.asMap().containsKey(key));
187      }
188      checkEmpty(cache);
189    }
190  }
191
192  public void testKeySet_populated() {
193    for (LoadingCache<Object, Object> cache : caches()) {
194      Set<Object> keys = cache.asMap().keySet();
195      List<Entry<Object, Object>> warmed = warmUp(cache);
196
197      Set<Object> expected = Maps.newHashMap(cache.asMap()).keySet();
198      assertThat(keys).has().exactlyAs(expected);
199      assertThat(keys.toArray()).asList().has().exactlyAs(expected);
200      assertThat(keys.toArray(new Object[0])).asList().has().exactlyAs(expected);
201
202      new EqualsTester()
203          .addEqualityGroup(cache.asMap().keySet(), keys)
204          .addEqualityGroup(ImmutableSet.of())
205          .testEquals();
206      assertEquals(WARMUP_SIZE, keys.size());
207      for (int i = WARMUP_MIN; i < WARMUP_MAX; i++) {
208        Object key = warmed.get(i - WARMUP_MIN).getKey();
209        assertTrue(keys.contains(key));
210        assertTrue(keys.remove(key));
211        assertFalse(keys.remove(key));
212        assertFalse(keys.contains(key));
213      }
214      checkEmpty(keys);
215      checkEmpty(cache);
216    }
217  }
218
219  public void testValues_populated() {
220    for (LoadingCache<Object, Object> cache : caches()) {
221      Collection<Object> values = cache.asMap().values();
222      List<Entry<Object, Object>> warmed = warmUp(cache);
223
224      Collection<Object> expected = Maps.newHashMap(cache.asMap()).values();
225      assertThat(values).has().exactlyAs(expected);
226      assertThat(values.toArray()).asList().has().exactlyAs(expected);
227      assertThat(values.toArray(new Object[0])).asList().has().exactlyAs(expected);
228
229      assertEquals(WARMUP_SIZE, values.size());
230      for (int i = WARMUP_MIN; i < WARMUP_MAX; i++) {
231        Object value = warmed.get(i - WARMUP_MIN).getValue();
232        assertTrue(values.contains(value));
233        assertTrue(values.remove(value));
234        assertFalse(values.remove(value));
235        assertFalse(values.contains(value));
236      }
237      checkEmpty(values);
238      checkEmpty(cache);
239    }
240  }
241
242  @SuppressWarnings("unchecked") // generic array creation
243
244  public void testEntrySet_populated() {
245    for (LoadingCache<Object, Object> cache : caches()) {
246      Set<Entry<Object, Object>> entries = cache.asMap().entrySet();
247      List<Entry<Object, Object>> warmed = warmUp(cache, WARMUP_MIN, WARMUP_MAX);
248
249      Set<?> expected = Maps.newHashMap(cache.asMap()).entrySet();
250      assertThat(entries).has().exactlyAs((Collection<Entry<Object, Object>>) expected);
251      assertThat(entries.toArray()).asList().has().exactlyAs((Collection<Object>) expected);
252      assertThat(entries.toArray(new Entry[0])).asList()
253          .has().exactlyAs((Collection<Entry>) expected);
254
255      new EqualsTester()
256          .addEqualityGroup(cache.asMap().entrySet(), entries)
257          .addEqualityGroup(ImmutableSet.of())
258          .testEquals();
259      assertEquals(WARMUP_SIZE, entries.size());
260      for (int i = WARMUP_MIN; i < WARMUP_MAX; i++) {
261        Entry<Object, Object> newEntry = warmed.get(i - WARMUP_MIN);
262        assertTrue(entries.contains(newEntry));
263        assertTrue(entries.remove(newEntry));
264        assertFalse(entries.remove(newEntry));
265        assertFalse(entries.contains(newEntry));
266      }
267      checkEmpty(entries);
268      checkEmpty(cache);
269    }
270  }
271
272  public void testWriteThroughEntry() {
273    for (LoadingCache<Object, Object> cache : caches()) {
274      cache.getUnchecked(1);
275      Entry<Object, Object> entry = Iterables.getOnlyElement(cache.asMap().entrySet());
276      try {
277        entry.setValue(3);
278        fail("expected entry.setValue to throw UnsupportedOperationException");
279      } catch (UnsupportedOperationException expected) {
280      }
281      try {
282        entry.setValue(null);
283        fail("expected entry.setValue(null) to throw UnsupportedOperationException");
284      } catch (UnsupportedOperationException expected) {
285      }
286      checkValidState(cache);
287    }
288  }
289
290  /* ---------------- Local utilities -------------- */
291
292  /**
293   * Most of the tests in this class run against every one of these caches.
294   */
295  private Iterable<LoadingCache<Object, Object>> caches() {
296    // lots of different ways to configure a LoadingCache
297    CacheBuilderFactory factory = cacheFactory();
298    return Iterables.transform(factory.buildAllPermutations(),
299        new Function<CacheBuilder<Object, Object>, LoadingCache<Object, Object>>() {
300          @Override public LoadingCache<Object, Object> apply(
301              CacheBuilder<Object, Object> builder) {
302            return builder.recordStats().build(identityLoader());
303          }
304        });
305  }
306
307  private CacheBuilderFactory cacheFactory() {
308    // This is trickier than expected. We plan to put 15 values in each of these (WARMUP_MIN to
309    // WARMUP_MAX), but the tests assume no values get evicted. Even with a maximumSize of 100, one
310    // of the values gets evicted. With weak keys, we use identity equality, which means using
311    // System.identityHashCode, which means the assignment of keys to segments is nondeterministic,
312    // so more than (maximumSize / #segments) keys could get assigned to the same segment, which
313    // would cause one to be evicted.
314    return new CacheBuilderFactory()
315        .withKeyStrengths(ImmutableSet.of(Strength.STRONG, Strength.WEAK))
316        .withValueStrengths(ImmutableSet.copyOf(Strength.values()))
317        .withConcurrencyLevels(ImmutableSet.of(1, 4, 16, 64))
318        .withMaximumSizes(ImmutableSet.of(400, 1000))
319        .withInitialCapacities(ImmutableSet.of(0, 1, 10, 100, 1000))
320        .withExpireAfterWrites(ImmutableSet.of(
321            // DurationSpec.of(500, MILLISECONDS),
322            DurationSpec.of(1, SECONDS),
323            DurationSpec.of(1, DAYS)))
324        .withExpireAfterAccesses(ImmutableSet.of(
325            // DurationSpec.of(500, MILLISECONDS),
326            DurationSpec.of(1, SECONDS),
327            DurationSpec.of(1, DAYS)))
328        .withRefreshes(ImmutableSet.of(
329            // DurationSpec.of(500, MILLISECONDS),
330            DurationSpec.of(1, SECONDS),
331            DurationSpec.of(1, DAYS)));
332  }
333
334  private List<Map.Entry<Object, Object>> warmUp(LoadingCache<Object, Object> cache) {
335    return warmUp(cache, WARMUP_MIN, WARMUP_MAX);
336  }
337
338  /**
339   * Returns the entries that were added to the map, so they won't fall out of a map with weak or
340   * soft references until the caller drops the reference to the returned entries.
341   */
342  private List<Map.Entry<Object, Object>> warmUp(
343      LoadingCache<Object, Object> cache, int minimum, int maximum) {
344
345    List<Map.Entry<Object, Object>> entries = Lists.newArrayList();
346    for (int i = minimum; i < maximum; i++) {
347      Object key = i;
348      Object value = cache.getUnchecked(key);
349      entries.add(entryOf(key, value));
350    }
351    return entries;
352  }
353
354  private Entry<Object, Object> entryOf(Object key, Object value) {
355    return Maps.immutableEntry(key, value);
356  }
357
358  private void assertMapSize(Map<?, ?> map, int size) {
359    assertEquals(size, map.size());
360    if (size > 0) {
361      assertFalse(map.isEmpty());
362    } else {
363      assertTrue(map.isEmpty());
364    }
365    assertCollectionSize(map.keySet(), size);
366    assertCollectionSize(map.entrySet(), size);
367    assertCollectionSize(map.values(), size);
368  }
369
370  private void assertCollectionSize(Collection<?> collection, int size) {
371    assertEquals(size, collection.size());
372    if (size > 0) {
373      assertFalse(collection.isEmpty());
374    } else {
375      assertTrue(collection.isEmpty());
376    }
377    assertEquals(size, Iterables.size(collection));
378    assertEquals(size, Iterators.size(collection.iterator()));
379  }
380}
381