/*
* 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.CacheBuilder.EMPTY_STATS;
import static com.google.common.cache.LocalCacheTest.SMALL_MAX_SIZE;
import static com.google.common.cache.TestingCacheLoaders.identityLoader;
import static org.junit.contrib.truth.Truth.ASSERT;
import com.google.common.cache.LocalCache.LocalLoadingCache;
import com.google.common.cache.LocalCache.Segment;
import com.google.common.collect.ImmutableMap;
import com.google.common.collect.ImmutableSet;
import com.google.common.collect.Maps;
import com.google.common.testing.NullPointerTester;
import com.google.common.util.concurrent.Callables;
import junit.framework.TestCase;
import java.lang.Thread.UncaughtExceptionHandler;
import java.util.Collection;
import java.util.Map;
import java.util.Set;
import java.util.concurrent.Callable;
import java.util.concurrent.ConcurrentMap;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicReference;
/**
* @author Charles Fry
*/
public class LocalLoadingCacheTest extends TestCase {
private static <K, V> LocalLoadingCache<K, V> makeCache(
CacheBuilder<K, V> builder, CacheLoader<? super K, V> loader) {
return new LocalLoadingCache<K, V>(builder, loader);
}
private CacheBuilder<Object, Object> createCacheBuilder() {
return CacheBuilder.newBuilder().recordStats();
}
// constructor tests
public void testComputingFunction() {
CacheLoader<Object, Object> loader = new CacheLoader<Object, Object>() {
@Override
public Object load(Object from) {
return new Object();
}
};
LocalLoadingCache<Object, Object> cache = makeCache(createCacheBuilder(), loader);
assertSame(loader, cache.localCache.defaultLoader);
}
// null parameters test
public void testNullParameters() throws Exception {
NullPointerTester tester = new NullPointerTester();
tester.setDefault(Callable.class, Callables.returning(null));
CacheLoader<Object, Object> loader = identityLoader();
tester.testAllPublicInstanceMethods(makeCache(createCacheBuilder(), loader));
}
// stats tests
public void testStats() {
CacheBuilder<Object, Object> builder = createCacheBuilder()
.concurrencyLevel(1)
.maximumSize(2);
LocalLoadingCache<Object, Object> cache = makeCache(builder, identityLoader());
assertEquals(EMPTY_STATS, cache.stats());
Object one = new Object();
cache.getUnchecked(one);
CacheStats stats = cache.stats();
assertEquals(1, stats.requestCount());
assertEquals(0, stats.hitCount());
assertEquals(0.0, stats.hitRate());
assertEquals(1, stats.missCount());
assertEquals(1.0, stats.missRate());
assertEquals(1, stats.loadCount());
long totalLoadTime = stats.totalLoadTime();
assertTrue(totalLoadTime > 0);
assertTrue(stats.averageLoadPenalty() > 0.0);
assertEquals(0, stats.evictionCount());
cache.getUnchecked(one);
stats = cache.stats();
assertEquals(2, stats.requestCount());
assertEquals(1, stats.hitCount());
assertEquals(1.0/2, stats.hitRate());
assertEquals(1, stats.missCount());
assertEquals(1.0/2, stats.missRate());
assertEquals(1, stats.loadCount());
assertEquals(0, stats.evictionCount());
Object two = new Object();
cache.getUnchecked(two);
stats = cache.stats();
assertEquals(3, stats.requestCount());
assertEquals(1, stats.hitCount());
assertEquals(1.0/3, stats.hitRate());
assertEquals(2, stats.missCount());
assertEquals(2.0/3, stats.missRate());
assertEquals(2, stats.loadCount());
assertTrue(stats.totalLoadTime() > totalLoadTime);
totalLoadTime = stats.totalLoadTime();
assertTrue(stats.averageLoadPenalty() > 0.0);
assertEquals(0, stats.evictionCount());
Object three = new Object();
cache.getUnchecked(three);
stats = cache.stats();
assertEquals(4, stats.requestCount());
assertEquals(1, stats.hitCount());
assertEquals(1.0/4, stats.hitRate());
assertEquals(3, stats.missCount());
assertEquals(3.0/4, stats.missRate());
assertEquals(3, stats.loadCount());
assertTrue(stats.totalLoadTime() > totalLoadTime);
totalLoadTime = stats.totalLoadTime();
assertTrue(stats.averageLoadPenalty() > 0.0);
assertEquals(1, stats.evictionCount());
}
public void testStatsNoops() {
CacheBuilder<Object, Object> builder = createCacheBuilder()
.concurrencyLevel(1);
LocalLoadingCache<Object, Object> cache = makeCache(builder, identityLoader());
ConcurrentMap<Object, Object> map = cache.localCache; // modifiable map view
assertEquals(EMPTY_STATS, cache.stats());
Object one = new Object();
assertNull(map.put(one, one));
assertSame(one, map.get(one));
assertTrue(map.containsKey(one));
assertTrue(map.containsValue(one));
Object two = new Object();
assertSame(one, map.replace(one, two));
assertTrue(map.containsKey(one));
assertFalse(map.containsValue(one));
Object three = new Object();
assertTrue(map.replace(one, two, three));
assertTrue(map.remove(one, three));
assertFalse(map.containsKey(one));
assertFalse(map.containsValue(one));
assertNull(map.putIfAbsent(two, three));
assertSame(three, map.remove(two));
assertNull(map.put(three, one));
assertNull(map.put(one, two));
Set<Map.Entry<Object, Object>> entries = map.entrySet();
ASSERT.that(entries).hasContentsAnyOrder(
Maps.immutableEntry(three, one), Maps.immutableEntry(one, two));
Set<Object> keys = map.keySet();
ASSERT.that(keys).hasContentsAnyOrder(one, three);
Collection<Object> values = map.values();
ASSERT.that(values).hasContentsAnyOrder(one, two);
map.clear();
assertEquals(EMPTY_STATS, cache.stats());
}
public void testNoStats() {
CacheBuilder<Object, Object> builder = CacheBuilder.newBuilder()
.concurrencyLevel(1)
.maximumSize(2);
LocalLoadingCache<Object, Object> cache = makeCache(builder, identityLoader());
assertEquals(EMPTY_STATS, cache.stats());
Object one = new Object();
cache.getUnchecked(one);
assertEquals(EMPTY_STATS, cache.stats());
cache.getUnchecked(one);
assertEquals(EMPTY_STATS, cache.stats());
Object two = new Object();
cache.getUnchecked(two);
assertEquals(EMPTY_STATS, cache.stats());
Object three = new Object();
cache.getUnchecked(three);
assertEquals(EMPTY_STATS, cache.stats());
}
public void testRecordStats() {
CacheBuilder<Object, Object> builder = createCacheBuilder()
.recordStats()
.concurrencyLevel(1)
.maximumSize(2);
LocalLoadingCache<Object, Object> cache = makeCache(builder, identityLoader());
assertEquals(0, cache.stats().hitCount());
assertEquals(0, cache.stats().missCount());
Object one = new Object();
cache.getUnchecked(one);
assertEquals(0, cache.stats().hitCount());
assertEquals(1, cache.stats().missCount());
cache.getUnchecked(one);
assertEquals(1, cache.stats().hitCount());
assertEquals(1, cache.stats().missCount());
Object two = new Object();
cache.getUnchecked(two);
assertEquals(1, cache.stats().hitCount());
assertEquals(2, cache.stats().missCount());
Object three = new Object();
cache.getUnchecked(three);
assertEquals(1, cache.stats().hitCount());
assertEquals(3, cache.stats().missCount());
}
// asMap tests
public void testAsMap() {
CacheBuilder<Object, Object> builder = createCacheBuilder();
LocalLoadingCache<Object, Object> cache = makeCache(builder, identityLoader());
assertEquals(EMPTY_STATS, cache.stats());
Object one = new Object();
Object two = new Object();
Object three = new Object();
ConcurrentMap<Object, Object> map = cache.asMap();
assertNull(map.put(one, two));
assertSame(two, map.get(one));
map.putAll(ImmutableMap.of(two, three));
assertSame(three, map.get(two));
assertSame(two, map.putIfAbsent(one, three));
assertSame(two, map.get(one));
assertNull(map.putIfAbsent(three, one));
assertSame(one, map.get(three));
assertSame(two, map.replace(one, three));
assertSame(three, map.get(one));
assertFalse(map.replace(one, two, three));
assertSame(three, map.get(one));
assertTrue(map.replace(one, three, two));
assertSame(two, map.get(one));
assertEquals(3, map.size());
map.clear();
assertTrue(map.isEmpty());
assertEquals(0, map.size());
cache.getUnchecked(one);
assertEquals(1, map.size());
assertSame(one, map.get(one));
assertTrue(map.containsKey(one));
assertTrue(map.containsValue(one));
assertSame(one, map.remove(one));
assertEquals(0, map.size());
cache.getUnchecked(one);
assertEquals(1, map.size());
assertFalse(map.remove(one, two));
assertTrue(map.remove(one, one));
assertEquals(0, map.size());
cache.getUnchecked(one);
Map<Object, Object> newMap = ImmutableMap.of(one, one);
assertEquals(newMap, map);
assertEquals(newMap.entrySet(), map.entrySet());
assertEquals(newMap.keySet(), map.keySet());
Set<Object> expectedValues = ImmutableSet.of(one);
Set<Object> actualValues = ImmutableSet.copyOf(map.values());
assertEquals(expectedValues, actualValues);
}
/**
* Lookups on the map view shouldn't impact the recency queue.
*/
public void testAsMapRecency() {
CacheBuilder<Object, Object> builder = createCacheBuilder()
.concurrencyLevel(1)
.maximumSize(SMALL_MAX_SIZE);
LocalLoadingCache<Object, Object> cache = makeCache(builder, identityLoader());
Segment<Object, Object> segment = cache.localCache.segments[0];
ConcurrentMap<Object, Object> map = cache.asMap();
Object one = new Object();
assertSame(one, cache.getUnchecked(one));
assertTrue(segment.recencyQueue.isEmpty());
assertSame(one, map.get(one));
assertSame(one, segment.recencyQueue.peek().getKey());
assertSame(one, cache.getUnchecked(one));
assertFalse(segment.recencyQueue.isEmpty());
}
public void testRecursiveComputation() throws InterruptedException {
final AtomicReference<LoadingCache<Integer, String>> cacheRef =
new AtomicReference<LoadingCache<Integer, String>>();
CacheLoader<Integer, String> recursiveLoader = new CacheLoader<Integer, String>() {
@Override
public String load(Integer key) {
if (key > 0) {
return key + ", " + cacheRef.get().getUnchecked(key - 1);
} else {
return "0";
}
}
};
LoadingCache<Integer, String> recursiveCache = new CacheBuilder<Integer, String>()
.weakKeys()
.weakValues()
.build(recursiveLoader);
cacheRef.set(recursiveCache);
assertEquals("3, 2, 1, 0", recursiveCache.getUnchecked(3));
recursiveLoader = new CacheLoader<Integer, String>() {
@Override
public String load(Integer key) {
return cacheRef.get().getUnchecked(key);
}
};
recursiveCache = new CacheBuilder<Integer, String>()
.weakKeys()
.weakValues()
.build(recursiveLoader);
cacheRef.set(recursiveCache);
// tells the test when the compution has completed
final CountDownLatch doneSignal = new CountDownLatch(1);
Thread thread = new Thread() {
@Override
public void run() {
try {
cacheRef.get().getUnchecked(3);
} finally {
doneSignal.countDown();
}
}
};
thread.setUncaughtExceptionHandler(new UncaughtExceptionHandler() {
@Override
public void uncaughtException(Thread t, Throwable e) {}
});
thread.start();
boolean done = doneSignal.await(1, TimeUnit.SECONDS);
if (!done) {
StringBuilder builder = new StringBuilder();
for (StackTraceElement trace : thread.getStackTrace()) {
builder.append("\tat ").append(trace).append('\n');
}
fail(builder.toString());
}
}
}