org.apache.jackrabbit.oak.plugins.document.TieredDiffCache Maven / Gradle / Ivy
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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.apache.jackrabbit.oak.plugins.document;
import javax.annotation.Nonnull;
import javax.annotation.Nullable;
import com.google.common.collect.Iterables;
import org.apache.jackrabbit.oak.cache.CacheStats;
/**
* Implements a tiered diff cache which consists of a {@link LocalDiffCache} and
* a {@link MemoryDiffCache}.
*/
class TieredDiffCache extends DiffCache {
private final DiffCache localCache;
private final DiffCache memoryCache;
TieredDiffCache(DocumentMK.Builder builder) {
this.localCache = new LocalDiffCache(builder);
this.memoryCache = new MemoryDiffCache(builder);
}
@Override
public String getChanges(@Nonnull RevisionVector from,
@Nonnull RevisionVector to,
@Nonnull String path,
@Nullable Loader loader) {
// check local first without loader
String changes = localCache.getChanges(from, to, path, null);
if (changes != null) {
return changes;
}
return memoryCache.getChanges(from, to, path, loader);
}
/**
* Creates a new entry in the {@link LocalDiffCache} for local changes
* and {@link MemoryDiffCache} for external changes
*
* @param from the from revision.
* @param to the to revision.
* @return the new entry.
*/
@Nonnull
@Override
public Entry newEntry(@Nonnull RevisionVector from, @Nonnull RevisionVector to, boolean local) {
if (local) {
return localCache.newEntry(from, to, true);
} else {
return memoryCache.newEntry(from, to, false);
}
}
@Nonnull
@Override
public Iterable getStats() {
return Iterables.concat(localCache.getStats(), memoryCache.getStats());
}
}