/*
* Copyright Terracotta, Inc.
*
* 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 org.ehcache.impl.internal.store.heap;
import org.ehcache.config.EvictionAdvisor;
import org.ehcache.core.spi.function.BiFunction;
import org.ehcache.core.spi.store.Store;
import org.ehcache.impl.internal.concurrent.ConcurrentHashMap;
import org.ehcache.impl.internal.store.heap.holders.OnHeapValueHolder;
import java.util.Comparator;
import java.util.Map;
import java.util.Random;
import java.util.concurrent.atomic.AtomicLong;
/**
* Simple passthrough backend, no key translation
*/
class SimpleBackend<K, V> implements Backend<K, V> {
private final ConcurrentHashMap<K, OnHeapValueHolder<V>> realMap;
private final boolean byteSized;
private final AtomicLong byteSize = new AtomicLong(0L);
SimpleBackend(boolean byteSized) {
this.byteSized = byteSized;
realMap = new ConcurrentHashMap<K, OnHeapValueHolder<V>>();
}
@Override
public boolean remove(K key, OnHeapValueHolder<V> value) {
return realMap.remove(key, value);
}
@Override
public Map.Entry<K, OnHeapValueHolder<V>> getEvictionCandidate(Random random, int size, final Comparator<? super Store.ValueHolder<V>> prioritizer, final EvictionAdvisor<Object, ? super OnHeapValueHolder<?>> evictionAdvisor) {
return realMap.getEvictionCandidate(random, size, prioritizer, evictionAdvisor);
}
@Override
public long mappingCount() {
return realMap.mappingCount();
}
@Override
public long byteSize() {
if (byteSized) {
return byteSize.get();
} else {
throw new IllegalStateException("This store is not byte sized");
}
}
@Override
public long naturalSize() {
if (byteSized) {
return byteSize.get();
} else {
return mappingCount();
}
}
@Override
public void updateUsageInBytesIfRequired(long delta) {
if (byteSized) {
byteSize.addAndGet(delta);
}
}
@Override
public Iterable<K> keySet() {
return realMap.keySet();
}
@Override
public java.util.Iterator<Map.Entry<K, OnHeapValueHolder<V>>> entrySetIterator() {
return realMap.entrySet().iterator();
}
@Override
public OnHeapValueHolder<V> compute(final K key, final BiFunction<K, OnHeapValueHolder<V>, OnHeapValueHolder<V>> computeFunction) {
return realMap.compute(key, computeFunction);
}
@Override
public Backend<K, V> clear() {
return new SimpleBackend<K, V>(byteSized);
}
@Override
public Map<K, OnHeapValueHolder<V>> removeAllWithHash(int hash) {
Map<K, OnHeapValueHolder<V>> removed = realMap.removeAllWithHash(hash);
if (byteSized) {
long delta = 0L;
for (Map.Entry<K, OnHeapValueHolder<V>> entry : removed.entrySet()) {
delta -= entry.getValue().size();
}
updateUsageInBytesIfRequired(delta);
}
return removed;
}
@Override
public OnHeapValueHolder<V> remove(K key) {
return realMap.remove(key);
}
@Override
public OnHeapValueHolder<V> computeIfPresent(final K key, final BiFunction<K, OnHeapValueHolder<V>, OnHeapValueHolder<V>> computeFunction) {
return realMap.computeIfPresent(key, computeFunction);
}
@Override
public OnHeapValueHolder<V> get(K key) {
return realMap.get(key);
}
@Override
public OnHeapValueHolder<V> putIfAbsent(K key, OnHeapValueHolder<V> valueHolder) {
return realMap.putIfAbsent(key, valueHolder);
}
@Override
public boolean replace(K key, OnHeapValueHolder<V> oldValue, OnHeapValueHolder<V> newValue) {
return realMap.replace(key, oldValue, newValue);
}
}