guava-tests/test/com/google/common/cache/PopulatedCachesTest.java - platform/external/guava - Git at Google

 /*
  * Copyright (C) 2011 The Guava Authors
  *
  * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
  * in compliance with the License. You may obtain a copy of the License at
  *
  * http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software distributed under the License
  * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
  * or implied. See the License for the specific language governing permissions and limitations under
  * the License.
  */

 package com.google.common.cache;

 import static com.google.common.cache.CacheTesting.checkEmpty;
 import static com.google.common.cache.CacheTesting.checkValidState;
 import static com.google.common.cache.TestingCacheLoaders.identityLoader;
 import static com.google.common.truth.Truth.assertThat;
 import static java.util.concurrent.TimeUnit.DAYS;
 import static java.util.concurrent.TimeUnit.SECONDS;

 import com.google.common.base.Function;
 import com.google.common.cache.CacheBuilderFactory.DurationSpec;
 import com.google.common.cache.LocalCache.Strength;
 import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.ImmutableSet;
 import com.google.common.collect.Iterables;
 import com.google.common.collect.Iterators;
 import com.google.common.collect.Lists;
 import com.google.common.collect.Maps;
 import com.google.common.testing.EqualsTester;
 import java.util.Collection;
 import java.util.List;
 import java.util.Map;
 import java.util.Map.Entry;
 import java.util.Set;
 import junit.framework.TestCase;

 /**
  * {@link LoadingCache} tests that deal with caches that actually contain some key-value mappings.
  *
  * @author mike nonemacher
  */

 public class PopulatedCachesTest extends TestCase {
   // we use integers as keys; make sure the range covers some values that ARE cached by
   // Integer.valueOf(int), and some that are not cached. (127 is the highest cached value.)
   static final int WARMUP_MIN = 120;
   static final int WARMUP_MAX = 135;
   static final int WARMUP_SIZE = WARMUP_MAX - WARMUP_MIN;

   public void testSize_populated() {
     for (LoadingCache<Object, Object> cache : caches()) {
       // don't let the entries get GCed
       List<Entry<Object, Object>> warmed = warmUp(cache);
       assertEquals(WARMUP_SIZE, cache.size());
       assertMapSize(cache.asMap(), WARMUP_SIZE);
       checkValidState(cache);
     }
   }

   public void testContainsKey_found() {
     for (LoadingCache<Object, Object> cache : caches()) {
       // don't let the entries get GCed
       List<Entry<Object, Object>> warmed = warmUp(cache);
       for (int i = WARMUP_MIN; i < WARMUP_MAX; i++) {
         Entry<Object, Object> entry = warmed.get(i - WARMUP_MIN);
         assertTrue(cache.asMap().containsKey(entry.getKey()));
         assertTrue(cache.asMap().containsValue(entry.getValue()));
         // this getUnchecked() call shouldn't be a cache miss; verified below
         assertEquals(entry.getValue(), cache.getUnchecked(entry.getKey()));
       }
       assertEquals(WARMUP_SIZE, cache.stats().missCount());
       checkValidState(cache);
     }
   }

   public void testPut_populated() {
     for (LoadingCache<Object, Object> cache : caches()) {
       // don't let the entries get GCed
       List<Entry<Object, Object>> warmed = warmUp(cache);
       for (int i = WARMUP_MIN; i < WARMUP_MAX; i++) {
         Entry<Object, Object> entry = warmed.get(i - WARMUP_MIN);
         Object newValue = new Object();
         assertSame(entry.getValue(), cache.asMap().put(entry.getKey(), newValue));
         // don't let the new entry get GCed
         warmed.add(entryOf(entry.getKey(), newValue));
         Object newKey = new Object();
         assertNull(cache.asMap().put(newKey, entry.getValue()));
         // this getUnchecked() call shouldn't be a cache miss; verified below
         assertEquals(newValue, cache.getUnchecked(entry.getKey()));
         assertEquals(entry.getValue(), cache.getUnchecked(newKey));
         // don't let the new entry get GCed
         warmed.add(entryOf(newKey, entry.getValue()));
       }
       assertEquals(WARMUP_SIZE, cache.stats().missCount());
       checkValidState(cache);
     }
   }

   public void testPutIfAbsent_populated() {
     for (LoadingCache<Object, Object> cache : caches()) {
       // don't let the entries get GCed
       List<Entry<Object, Object>> warmed = warmUp(cache);
       for (int i = WARMUP_MIN; i < WARMUP_MAX; i++) {
         Entry<Object, Object> entry = warmed.get(i - WARMUP_MIN);
         Object newValue = new Object();
         assertSame(entry.getValue(), cache.asMap().putIfAbsent(entry.getKey(), newValue));
         Object newKey = new Object();
         assertNull(cache.asMap().putIfAbsent(newKey, entry.getValue()));
         // this getUnchecked() call shouldn't be a cache miss; verified below
         assertEquals(entry.getValue(), cache.getUnchecked(entry.getKey()));
         assertEquals(entry.getValue(), cache.getUnchecked(newKey));
         // don't let the new entry get GCed
         warmed.add(entryOf(newKey, entry.getValue()));
       }
       assertEquals(WARMUP_SIZE, cache.stats().missCount());
       checkValidState(cache);
     }
   }

   public void testPutAll_populated() {
     for (LoadingCache<Object, Object> cache : caches()) {
       // don't let the entries get GCed
       List<Entry<Object, Object>> warmed = warmUp(cache);
       Object newKey = new Object();
       Object newValue = new Object();
       cache.asMap().putAll(ImmutableMap.of(newKey, newValue));
       // this getUnchecked() call shouldn't be a cache miss; verified below
       assertEquals(newValue, cache.getUnchecked(newKey));
       assertEquals(WARMUP_SIZE, cache.stats().missCount());
       checkValidState(cache);
     }
   }

   public void testReplace_populated() {
     for (LoadingCache<Object, Object> cache : caches()) {
       // don't let the entries get GCed
       List<Entry<Object, Object>> warmed = warmUp(cache);
       for (int i = WARMUP_MIN; i < WARMUP_MAX; i++) {
         Entry<Object, Object> entry = warmed.get(i - WARMUP_MIN);
         Object newValue = new Object();
         assertSame(entry.getValue(), cache.asMap().replace(entry.getKey(), newValue));
         assertTrue(cache.asMap().replace(entry.getKey(), newValue, entry.getValue()));
         Object newKey = new Object();
         assertNull(cache.asMap().replace(newKey, entry.getValue()));
         assertFalse(cache.asMap().replace(newKey, entry.getValue(), newValue));
         // this getUnchecked() call shouldn't be a cache miss; verified below
         assertEquals(entry.getValue(), cache.getUnchecked(entry.getKey()));
         assertFalse(cache.asMap().containsKey(newKey));
       }
       assertEquals(WARMUP_SIZE, cache.stats().missCount());
       checkValidState(cache);
     }
   }

   public void testRemove_byKey() {
     for (LoadingCache<Object, Object> cache : caches()) {
       // don't let the entries get GCed
       List<Entry<Object, Object>> warmed = warmUp(cache);
       for (int i = WARMUP_MIN; i < WARMUP_MAX; i++) {
         Entry<Object, Object> entry = warmed.get(i - WARMUP_MIN);
         Object key = entry.getKey();
         assertEquals(entry.getValue(), cache.asMap().remove(key));
         assertNull(cache.asMap().remove(key));
         assertFalse(cache.asMap().containsKey(key));
       }
       checkEmpty(cache);
     }
   }

   public void testRemove_byKeyAndValue() {
     for (LoadingCache<Object, Object> cache : caches()) {
       // don't let the entries get GCed
       List<Entry<Object, Object>> warmed = warmUp(cache);
       for (int i = WARMUP_MIN; i < WARMUP_MAX; i++) {
         Object key = warmed.get(i - WARMUP_MIN).getKey();
         Object value = warmed.get(i - WARMUP_MIN).getValue();
         assertFalse(cache.asMap().remove(key, -1));
         assertTrue(cache.asMap().remove(key, value));
         assertFalse(cache.asMap().remove(key, -1));
         assertFalse(cache.asMap().containsKey(key));
       }
       checkEmpty(cache);
     }
   }

   public void testKeySet_populated() {
     for (LoadingCache<Object, Object> cache : caches()) {
       Set<Object> keys = cache.asMap().keySet();
       List<Entry<Object, Object>> warmed = warmUp(cache);

       Set<Object> expected = Maps.newHashMap(cache.asMap()).keySet();
       assertThat(keys).containsExactlyElementsIn(expected);
       assertThat(keys.toArray()).asList().containsExactlyElementsIn(expected);
       assertThat(keys.toArray(new Object[0])).asList().containsExactlyElementsIn(expected);

       new EqualsTester()
           .addEqualityGroup(cache.asMap().keySet(), keys)
           .addEqualityGroup(ImmutableSet.of())
           .testEquals();
       assertEquals(WARMUP_SIZE, keys.size());
       for (int i = WARMUP_MIN; i < WARMUP_MAX; i++) {
         Object key = warmed.get(i - WARMUP_MIN).getKey();
         assertTrue(keys.contains(key));
         assertTrue(keys.remove(key));
         assertFalse(keys.remove(key));
         assertFalse(keys.contains(key));
       }
       checkEmpty(keys);
       checkEmpty(cache);
     }
   }

   public void testValues_populated() {
     for (LoadingCache<Object, Object> cache : caches()) {
       Collection<Object> values = cache.asMap().values();
       List<Entry<Object, Object>> warmed = warmUp(cache);

       Collection<Object> expected = Maps.newHashMap(cache.asMap()).values();
       assertThat(values).containsExactlyElementsIn(expected);
       assertThat(values.toArray()).asList().containsExactlyElementsIn(expected);
       assertThat(values.toArray(new Object[0])).asList().containsExactlyElementsIn(expected);

       assertEquals(WARMUP_SIZE, values.size());
       for (int i = WARMUP_MIN; i < WARMUP_MAX; i++) {
         Object value = warmed.get(i - WARMUP_MIN).getValue();
         assertTrue(values.contains(value));
         assertTrue(values.remove(value));
         assertFalse(values.remove(value));
         assertFalse(values.contains(value));
       }
       checkEmpty(values);
       checkEmpty(cache);
     }
   }

   public void testEntrySet_populated() {
     for (LoadingCache<Object, Object> cache : caches()) {
       Set<Entry<Object, Object>> entries = cache.asMap().entrySet();
       List<Entry<Object, Object>> warmed = warmUp(cache, WARMUP_MIN, WARMUP_MAX);

       Set<?> expected = Maps.newHashMap(cache.asMap()).entrySet();
       assertThat(entries).containsExactlyElementsIn(expected);
       assertThat(entries.toArray()).asList().containsExactlyElementsIn(expected);
       assertThat(entries.toArray(new Object[0])).asList().containsExactlyElementsIn(expected);

       new EqualsTester()
           .addEqualityGroup(cache.asMap().entrySet(), entries)
           .addEqualityGroup(ImmutableSet.of())
           .testEquals();
       assertEquals(WARMUP_SIZE, entries.size());
       for (int i = WARMUP_MIN; i < WARMUP_MAX; i++) {
         Entry<Object, Object> newEntry = warmed.get(i - WARMUP_MIN);
         assertTrue(entries.contains(newEntry));
         assertTrue(entries.remove(newEntry));
         assertFalse(entries.remove(newEntry));
         assertFalse(entries.contains(newEntry));
       }
       checkEmpty(entries);
       checkEmpty(cache);
     }
   }

   public void testWriteThroughEntry() {
     for (LoadingCache<Object, Object> cache : caches()) {
       cache.getUnchecked(1);
       Entry<Object, Object> entry = Iterables.getOnlyElement(cache.asMap().entrySet());

       cache.invalidate(1);
       assertEquals(0, cache.size());

       entry.setValue(3);
       assertEquals(1, cache.size());
       assertEquals(3, cache.getIfPresent(1));
       checkValidState(cache);

       try {
         entry.setValue(null);
         fail();
       } catch (NullPointerException expected) {
       }
       checkValidState(cache);
     }
   }

   /* ---------------- Local utilities -------------- */

   /** Most of the tests in this class run against every one of these caches. */
   private Iterable<LoadingCache<Object, Object>> caches() {
     // lots of different ways to configure a LoadingCache
     CacheBuilderFactory factory = cacheFactory();
     return Iterables.transform(
         factory.buildAllPermutations(),
         new Function<CacheBuilder<Object, Object>, LoadingCache<Object, Object>>() {
           @Override
           public LoadingCache<Object, Object> apply(CacheBuilder<Object, Object> builder) {
             return builder.recordStats().build(identityLoader());
           }
         });
   }

   private CacheBuilderFactory cacheFactory() {
     // This is trickier than expected. We plan to put 15 values in each of these (WARMUP_MIN to
     // WARMUP_MAX), but the tests assume no values get evicted. Even with a maximumSize of 100, one
     // of the values gets evicted. With weak keys, we use identity equality, which means using
     // System.identityHashCode, which means the assignment of keys to segments is nondeterministic,
     // so more than (maximumSize / #segments) keys could get assigned to the same segment, which
     // would cause one to be evicted.
     return new CacheBuilderFactory()
         .withKeyStrengths(ImmutableSet.of(Strength.STRONG, Strength.WEAK))
         .withValueStrengths(ImmutableSet.copyOf(Strength.values()))
         .withConcurrencyLevels(ImmutableSet.of(1, 4, 16, 64))
         .withMaximumSizes(ImmutableSet.of(400, 1000))
         .withInitialCapacities(ImmutableSet.of(0, 1, 10, 100, 1000))
         .withExpireAfterWrites(
             ImmutableSet.of(
                 // DurationSpec.of(500, MILLISECONDS),
                 DurationSpec.of(1, SECONDS), DurationSpec.of(1, DAYS)))
         .withExpireAfterAccesses(
             ImmutableSet.of(
                 // DurationSpec.of(500, MILLISECONDS),
                 DurationSpec.of(1, SECONDS), DurationSpec.of(1, DAYS)))
         .withRefreshes(
             ImmutableSet.of(
                 // DurationSpec.of(500, MILLISECONDS),
                 DurationSpec.of(1, SECONDS), DurationSpec.of(1, DAYS)));
   }

   private List<Entry<Object, Object>> warmUp(LoadingCache<Object, Object> cache) {
     return warmUp(cache, WARMUP_MIN, WARMUP_MAX);
   }

   /**
    * Returns the entries that were added to the map, so they won't fall out of a map with weak or
    * soft references until the caller drops the reference to the returned entries.
    */
   private List<Entry<Object, Object>> warmUp(
       LoadingCache<Object, Object> cache, int minimum, int maximum) {

     List<Entry<Object, Object>> entries = Lists.newArrayList();
     for (int i = minimum; i < maximum; i++) {
       Object key = i;
       Object value = cache.getUnchecked(key);
       entries.add(entryOf(key, value));
     }
     return entries;
   }

   private Entry<Object, Object> entryOf(Object key, Object value) {
     return Maps.immutableEntry(key, value);
   }

   private void assertMapSize(Map<?, ?> map, int size) {
     assertEquals(size, map.size());
     if (size > 0) {
       assertFalse(map.isEmpty());
     } else {
       assertTrue(map.isEmpty());
     }
     assertCollectionSize(map.keySet(), size);
     assertCollectionSize(map.entrySet(), size);
     assertCollectionSize(map.values(), size);
   }

   private void assertCollectionSize(Collection<?> collection, int size) {
     assertEquals(size, collection.size());
     if (size > 0) {
       assertFalse(collection.isEmpty());
     } else {
       assertTrue(collection.isEmpty());
     }
     assertEquals(size, Iterables.size(collection));
     assertEquals(size, Iterators.size(collection.iterator()));
   }
 }
	/*
	* Copyright (C) 2011 The Guava Authors
	*
	* Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
	* in compliance with the License. You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software distributed under the License
	* is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
	* or implied. See the License for the specific language governing permissions and limitations under
	* the License.
	*/

	package com.google.common.cache;

	import static com.google.common.cache.CacheTesting.checkEmpty;
	import static com.google.common.cache.CacheTesting.checkValidState;
	import static com.google.common.cache.TestingCacheLoaders.identityLoader;
	import static com.google.common.truth.Truth.assertThat;
	import static java.util.concurrent.TimeUnit.DAYS;
	import static java.util.concurrent.TimeUnit.SECONDS;

	import com.google.common.base.Function;
	import com.google.common.cache.CacheBuilderFactory.DurationSpec;
	import com.google.common.cache.LocalCache.Strength;
	import com.google.common.collect.ImmutableMap;
	import com.google.common.collect.ImmutableSet;
	import com.google.common.collect.Iterables;
	import com.google.common.collect.Iterators;
	import com.google.common.collect.Lists;
	import com.google.common.collect.Maps;
	import com.google.common.testing.EqualsTester;
	import java.util.Collection;
	import java.util.List;
	import java.util.Map;
	import java.util.Map.Entry;
	import java.util.Set;
	import junit.framework.TestCase;

	/**
	* {@link LoadingCache} tests that deal with caches that actually contain some key-value mappings.
	*
	* @author mike nonemacher
	*/

	public class PopulatedCachesTest extends TestCase {
	// we use integers as keys; make sure the range covers some values that ARE cached by
	// Integer.valueOf(int), and some that are not cached. (127 is the highest cached value.)
	static final int WARMUP_MIN = 120;
	static final int WARMUP_MAX = 135;
	static final int WARMUP_SIZE = WARMUP_MAX - WARMUP_MIN;

	public void testSize_populated() {
	for (LoadingCache<Object, Object> cache : caches()) {
	// don't let the entries get GCed
	List<Entry<Object, Object>> warmed = warmUp(cache);
	assertEquals(WARMUP_SIZE, cache.size());
	assertMapSize(cache.asMap(), WARMUP_SIZE);
	checkValidState(cache);
	}
	}

	public void testContainsKey_found() {
	for (LoadingCache<Object, Object> cache : caches()) {
	// don't let the entries get GCed
	List<Entry<Object, Object>> warmed = warmUp(cache);
	for (int i = WARMUP_MIN; i < WARMUP_MAX; i++) {
	Entry<Object, Object> entry = warmed.get(i - WARMUP_MIN);
	assertTrue(cache.asMap().containsKey(entry.getKey()));
	assertTrue(cache.asMap().containsValue(entry.getValue()));
	// this getUnchecked() call shouldn't be a cache miss; verified below
	assertEquals(entry.getValue(), cache.getUnchecked(entry.getKey()));
	}
	assertEquals(WARMUP_SIZE, cache.stats().missCount());
	checkValidState(cache);
	}
	}

	public void testPut_populated() {
	for (LoadingCache<Object, Object> cache : caches()) {
	// don't let the entries get GCed
	List<Entry<Object, Object>> warmed = warmUp(cache);
	for (int i = WARMUP_MIN; i < WARMUP_MAX; i++) {
	Entry<Object, Object> entry = warmed.get(i - WARMUP_MIN);
	Object newValue = new Object();
	assertSame(entry.getValue(), cache.asMap().put(entry.getKey(), newValue));
	// don't let the new entry get GCed
	warmed.add(entryOf(entry.getKey(), newValue));
	Object newKey = new Object();
	assertNull(cache.asMap().put(newKey, entry.getValue()));
	// this getUnchecked() call shouldn't be a cache miss; verified below
	assertEquals(newValue, cache.getUnchecked(entry.getKey()));
	assertEquals(entry.getValue(), cache.getUnchecked(newKey));
	// don't let the new entry get GCed
	warmed.add(entryOf(newKey, entry.getValue()));
	}
	assertEquals(WARMUP_SIZE, cache.stats().missCount());
	checkValidState(cache);
	}
	}

	public void testPutIfAbsent_populated() {
	for (LoadingCache<Object, Object> cache : caches()) {
	// don't let the entries get GCed
	List<Entry<Object, Object>> warmed = warmUp(cache);
	for (int i = WARMUP_MIN; i < WARMUP_MAX; i++) {
	Entry<Object, Object> entry = warmed.get(i - WARMUP_MIN);
	Object newValue = new Object();
	assertSame(entry.getValue(), cache.asMap().putIfAbsent(entry.getKey(), newValue));
	Object newKey = new Object();
	assertNull(cache.asMap().putIfAbsent(newKey, entry.getValue()));
	// this getUnchecked() call shouldn't be a cache miss; verified below
	assertEquals(entry.getValue(), cache.getUnchecked(entry.getKey()));
	assertEquals(entry.getValue(), cache.getUnchecked(newKey));
	// don't let the new entry get GCed
	warmed.add(entryOf(newKey, entry.getValue()));
	}
	assertEquals(WARMUP_SIZE, cache.stats().missCount());
	checkValidState(cache);
	}
	}

	public void testPutAll_populated() {
	for (LoadingCache<Object, Object> cache : caches()) {
	// don't let the entries get GCed
	List<Entry<Object, Object>> warmed = warmUp(cache);
	Object newKey = new Object();
	Object newValue = new Object();
	cache.asMap().putAll(ImmutableMap.of(newKey, newValue));
	// this getUnchecked() call shouldn't be a cache miss; verified below
	assertEquals(newValue, cache.getUnchecked(newKey));
	assertEquals(WARMUP_SIZE, cache.stats().missCount());
	checkValidState(cache);
	}
	}

	public void testReplace_populated() {
	for (LoadingCache<Object, Object> cache : caches()) {
	// don't let the entries get GCed
	List<Entry<Object, Object>> warmed = warmUp(cache);
	for (int i = WARMUP_MIN; i < WARMUP_MAX; i++) {
	Entry<Object, Object> entry = warmed.get(i - WARMUP_MIN);
	Object newValue = new Object();
	assertSame(entry.getValue(), cache.asMap().replace(entry.getKey(), newValue));
	assertTrue(cache.asMap().replace(entry.getKey(), newValue, entry.getValue()));
	Object newKey = new Object();
	assertNull(cache.asMap().replace(newKey, entry.getValue()));
	assertFalse(cache.asMap().replace(newKey, entry.getValue(), newValue));
	// this getUnchecked() call shouldn't be a cache miss; verified below
	assertEquals(entry.getValue(), cache.getUnchecked(entry.getKey()));
	assertFalse(cache.asMap().containsKey(newKey));
	}
	assertEquals(WARMUP_SIZE, cache.stats().missCount());
	checkValidState(cache);
	}
	}

	public void testRemove_byKey() {
	for (LoadingCache<Object, Object> cache : caches()) {
	// don't let the entries get GCed
	List<Entry<Object, Object>> warmed = warmUp(cache);
	for (int i = WARMUP_MIN; i < WARMUP_MAX; i++) {
	Entry<Object, Object> entry = warmed.get(i - WARMUP_MIN);
	Object key = entry.getKey();
	assertEquals(entry.getValue(), cache.asMap().remove(key));
	assertNull(cache.asMap().remove(key));
	assertFalse(cache.asMap().containsKey(key));
	}
	checkEmpty(cache);
	}
	}

	public void testRemove_byKeyAndValue() {
	for (LoadingCache<Object, Object> cache : caches()) {
	// don't let the entries get GCed
	List<Entry<Object, Object>> warmed = warmUp(cache);
	for (int i = WARMUP_MIN; i < WARMUP_MAX; i++) {
	Object key = warmed.get(i - WARMUP_MIN).getKey();
	Object value = warmed.get(i - WARMUP_MIN).getValue();
	assertFalse(cache.asMap().remove(key, -1));
	assertTrue(cache.asMap().remove(key, value));
	assertFalse(cache.asMap().remove(key, -1));
	assertFalse(cache.asMap().containsKey(key));
	}
	checkEmpty(cache);
	}
	}

	public void testKeySet_populated() {
	for (LoadingCache<Object, Object> cache : caches()) {
	Set<Object> keys = cache.asMap().keySet();
	List<Entry<Object, Object>> warmed = warmUp(cache);

	Set<Object> expected = Maps.newHashMap(cache.asMap()).keySet();
	assertThat(keys).containsExactlyElementsIn(expected);
	assertThat(keys.toArray()).asList().containsExactlyElementsIn(expected);
	assertThat(keys.toArray(new Object[0])).asList().containsExactlyElementsIn(expected);

	new EqualsTester()
	.addEqualityGroup(cache.asMap().keySet(), keys)
	.addEqualityGroup(ImmutableSet.of())
	.testEquals();
	assertEquals(WARMUP_SIZE, keys.size());
	for (int i = WARMUP_MIN; i < WARMUP_MAX; i++) {
	Object key = warmed.get(i - WARMUP_MIN).getKey();
	assertTrue(keys.contains(key));
	assertTrue(keys.remove(key));
	assertFalse(keys.remove(key));
	assertFalse(keys.contains(key));
	}
	checkEmpty(keys);
	checkEmpty(cache);
	}
	}

	public void testValues_populated() {
	for (LoadingCache<Object, Object> cache : caches()) {
	Collection<Object> values = cache.asMap().values();
	List<Entry<Object, Object>> warmed = warmUp(cache);

	Collection<Object> expected = Maps.newHashMap(cache.asMap()).values();
	assertThat(values).containsExactlyElementsIn(expected);
	assertThat(values.toArray()).asList().containsExactlyElementsIn(expected);
	assertThat(values.toArray(new Object[0])).asList().containsExactlyElementsIn(expected);

	assertEquals(WARMUP_SIZE, values.size());
	for (int i = WARMUP_MIN; i < WARMUP_MAX; i++) {
	Object value = warmed.get(i - WARMUP_MIN).getValue();
	assertTrue(values.contains(value));
	assertTrue(values.remove(value));
	assertFalse(values.remove(value));
	assertFalse(values.contains(value));
	}
	checkEmpty(values);
	checkEmpty(cache);
	}
	}

	public void testEntrySet_populated() {
	for (LoadingCache<Object, Object> cache : caches()) {
	Set<Entry<Object, Object>> entries = cache.asMap().entrySet();
	List<Entry<Object, Object>> warmed = warmUp(cache, WARMUP_MIN, WARMUP_MAX);

	Set<?> expected = Maps.newHashMap(cache.asMap()).entrySet();
	assertThat(entries).containsExactlyElementsIn(expected);
	assertThat(entries.toArray()).asList().containsExactlyElementsIn(expected);
	assertThat(entries.toArray(new Object[0])).asList().containsExactlyElementsIn(expected);

	new EqualsTester()
	.addEqualityGroup(cache.asMap().entrySet(), entries)
	.addEqualityGroup(ImmutableSet.of())
	.testEquals();
	assertEquals(WARMUP_SIZE, entries.size());
	for (int i = WARMUP_MIN; i < WARMUP_MAX; i++) {
	Entry<Object, Object> newEntry = warmed.get(i - WARMUP_MIN);
	assertTrue(entries.contains(newEntry));
	assertTrue(entries.remove(newEntry));
	assertFalse(entries.remove(newEntry));
	assertFalse(entries.contains(newEntry));
	}
	checkEmpty(entries);
	checkEmpty(cache);
	}
	}

	public void testWriteThroughEntry() {
	for (LoadingCache<Object, Object> cache : caches()) {
	cache.getUnchecked(1);
	Entry<Object, Object> entry = Iterables.getOnlyElement(cache.asMap().entrySet());

	cache.invalidate(1);
	assertEquals(0, cache.size());

	entry.setValue(3);
	assertEquals(1, cache.size());
	assertEquals(3, cache.getIfPresent(1));
	checkValidState(cache);

	try {
	entry.setValue(null);
	fail();
	} catch (NullPointerException expected) {
	}
	checkValidState(cache);
	}
	}

	/* ---------------- Local utilities -------------- */

	/** Most of the tests in this class run against every one of these caches. */
	private Iterable<LoadingCache<Object, Object>> caches() {
	// lots of different ways to configure a LoadingCache
	CacheBuilderFactory factory = cacheFactory();
	return Iterables.transform(
	factory.buildAllPermutations(),
	new Function<CacheBuilder<Object, Object>, LoadingCache<Object, Object>>() {
	@Override
	public LoadingCache<Object, Object> apply(CacheBuilder<Object, Object> builder) {
	return builder.recordStats().build(identityLoader());
	}
	});
	}

	private CacheBuilderFactory cacheFactory() {
	// This is trickier than expected. We plan to put 15 values in each of these (WARMUP_MIN to
	// WARMUP_MAX), but the tests assume no values get evicted. Even with a maximumSize of 100, one
	// of the values gets evicted. With weak keys, we use identity equality, which means using
	// System.identityHashCode, which means the assignment of keys to segments is nondeterministic,
	// so more than (maximumSize / #segments) keys could get assigned to the same segment, which
	// would cause one to be evicted.
	return new CacheBuilderFactory()
	.withKeyStrengths(ImmutableSet.of(Strength.STRONG, Strength.WEAK))
	.withValueStrengths(ImmutableSet.copyOf(Strength.values()))
	.withConcurrencyLevels(ImmutableSet.of(1, 4, 16, 64))
	.withMaximumSizes(ImmutableSet.of(400, 1000))
	.withInitialCapacities(ImmutableSet.of(0, 1, 10, 100, 1000))
	.withExpireAfterWrites(
	ImmutableSet.of(
	// DurationSpec.of(500, MILLISECONDS),
	DurationSpec.of(1, SECONDS), DurationSpec.of(1, DAYS)))
	.withExpireAfterAccesses(
	ImmutableSet.of(
	// DurationSpec.of(500, MILLISECONDS),
	DurationSpec.of(1, SECONDS), DurationSpec.of(1, DAYS)))
	.withRefreshes(
	ImmutableSet.of(
	// DurationSpec.of(500, MILLISECONDS),
	DurationSpec.of(1, SECONDS), DurationSpec.of(1, DAYS)));
	}

	private List<Entry<Object, Object>> warmUp(LoadingCache<Object, Object> cache) {
	return warmUp(cache, WARMUP_MIN, WARMUP_MAX);
	}

	/**
	* Returns the entries that were added to the map, so they won't fall out of a map with weak or
	* soft references until the caller drops the reference to the returned entries.
	*/
	private List<Entry<Object, Object>> warmUp(
	LoadingCache<Object, Object> cache, int minimum, int maximum) {

	List<Entry<Object, Object>> entries = Lists.newArrayList();
	for (int i = minimum; i < maximum; i++) {
	Object key = i;
	Object value = cache.getUnchecked(key);
	entries.add(entryOf(key, value));
	}
	return entries;
	}

	private Entry<Object, Object> entryOf(Object key, Object value) {
	return Maps.immutableEntry(key, value);
	}

	private void assertMapSize(Map<?, ?> map, int size) {
	assertEquals(size, map.size());
	if (size > 0) {
	assertFalse(map.isEmpty());
	} else {
	assertTrue(map.isEmpty());
	}
	assertCollectionSize(map.keySet(), size);
	assertCollectionSize(map.entrySet(), size);
	assertCollectionSize(map.values(), size);
	}

	private void assertCollectionSize(Collection<?> collection, int size) {
	assertEquals(size, collection.size());
	if (size > 0) {
	assertFalse(collection.isEmpty());
	} else {
	assertTrue(collection.isEmpty());
	}
	assertEquals(size, Iterables.size(collection));
	assertEquals(size, Iterators.size(collection.iterator()));
	}
	}