/*
* Copyright 2014 the original author or 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 org.gradle.cache.internal;
import org.gradle.api.Nullable;
import org.gradle.api.Transformer;
import org.gradle.internal.Factory;
/**
* Applies cross-process file locking to a backing cache, to ensure that any in-memory and on file state is kept in sync while this process is read from or writing to the cache.
*/
public class CrossProcessSynchronizingCache<K, V> implements MultiProcessSafePersistentIndexedCache<K, V> {
private final CrossProcessCacheAccess cacheAccess;
private final MultiProcessSafeAsyncPersistentIndexedCache<K, V> target;
public CrossProcessSynchronizingCache(MultiProcessSafeAsyncPersistentIndexedCache<K, V> target, CrossProcessCacheAccess cacheAccess) {
this.target = target;
this.cacheAccess = cacheAccess;
}
@Override
public String toString() {
return target.toString();
}
@Nullable
@Override
public V get(final K key) {
return cacheAccess.withFileLock(new Factory<V>() {
@Override
public V create() {
return target.get(key);
}
});
}
@Override
public V get(final K key, final Transformer<? extends V, ? super K> producer) {
Runnable runnable = cacheAccess.acquireFileLock();
return target.get(key, producer, runnable);
}
@Override
public void put(K key, V value) {
Runnable runnable = cacheAccess.acquireFileLock();
target.putLater(key, value, runnable);
}
@Override
public void remove(K key) {
Runnable runnable = cacheAccess.acquireFileLock();
target.removeLater(key, runnable);
}
@Override
public void afterLockAcquire(FileLock.State currentCacheState) {
target.afterLockAcquire(currentCacheState);
}
@Override
public void finishWork() {
target.finishWork();
}
@Override
public void beforeLockRelease(FileLock.State currentCacheState) {
target.beforeLockRelease(currentCacheState);
}
}