/*
* Copyright 2015 Ben Manes. All Rights Reserved.
*
* 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.github.benmanes.caffeine.jcache.spi;
import java.net.URI;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Map;
import java.util.Properties;
import java.util.WeakHashMap;
import javax.annotation.concurrent.GuardedBy;
import javax.cache.CacheManager;
import javax.cache.Caching;
import javax.cache.configuration.OptionalFeature;
import javax.cache.spi.CachingProvider;
import com.github.benmanes.caffeine.jcache.CacheManagerImpl;
/**
* A provider that produces a JCache implementation backed by Caffeine. Typically this provider is
* instantiated using {@link Caching#getCachingProvider()}, which discovers this implementation
* through a {@link java.util.ServiceLoader}.
* <p>
* This provider is expected to be used for application life cycle events, like initialization. It
* is not expected that all requests flow through the provider in obtain the cache manager and cache
* instances for request operations. Internally, this implementation is synchronized to avoid using
* excess memory due to its infrequent usage.
*
* @author ben.manes@gmail.com (Ben Manes)
*/
public final class CaffeineCachingProvider implements CachingProvider {
@GuardedBy("itself")
private final Map<ClassLoader, Map<URI, CacheManager>> cacheManagers;
public CaffeineCachingProvider() {
this.cacheManagers = new WeakHashMap<>(1);
}
@Override
public ClassLoader getDefaultClassLoader() {
return getClass().getClassLoader();
}
@Override
public URI getDefaultURI() {
return URI.create(getClass().getName());
}
@Override
public Properties getDefaultProperties() {
return new Properties();
}
@Override
public CacheManager getCacheManager() {
return getCacheManager(getDefaultURI(), getDefaultClassLoader());
}
@Override
public CacheManager getCacheManager(URI uri, ClassLoader classLoader) {
return getCacheManager(uri, classLoader, getDefaultProperties());
}
@Override
public CacheManager getCacheManager(URI uri, ClassLoader classLoader, Properties properties) {
URI managerURI = getManagerUri(uri);
ClassLoader managerClassLoader = getManagerClassLoader(classLoader);
synchronized (cacheManagers) {
Map<URI, CacheManager> cacheManagersByURI = cacheManagers.computeIfAbsent(
managerClassLoader, any -> new HashMap<>());
return cacheManagersByURI.computeIfAbsent(managerURI, any -> {
Properties managerProperties = (properties == null) ? getDefaultProperties() : properties;
return new CacheManagerImpl(this, managerURI, managerClassLoader, managerProperties);
});
}
}
@Override
public void close() {
synchronized (cacheManagers) {
for (ClassLoader classLoader : new ArrayList<>(cacheManagers.keySet())) {
close(classLoader);
}
}
}
@Override
public void close(ClassLoader classLoader) {
synchronized (cacheManagers) {
ClassLoader managerClassLoader = getManagerClassLoader(classLoader);
Map<URI, CacheManager> cacheManagersByURI = cacheManagers.remove(managerClassLoader);
if (cacheManagersByURI != null) {
for (CacheManager cacheManager : cacheManagersByURI.values()) {
cacheManager.close();
}
}
}
}
@Override
public void close(URI uri, ClassLoader classLoader) {
synchronized (cacheManagers) {
ClassLoader managerClassLoader = getManagerClassLoader(classLoader);
Map<URI, CacheManager> cacheManagersByURI = cacheManagers.get(managerClassLoader);
if (cacheManagersByURI != null) {
CacheManager cacheManager = cacheManagersByURI.remove(getManagerUri(uri));
if (cacheManager != null) {
cacheManager.close();
}
if (cacheManagersByURI.isEmpty()) {
cacheManagers.remove(managerClassLoader);
}
}
}
}
@Override
@SuppressWarnings("PMD.TooFewBranchesForASwitchStatement")
public boolean isSupported(OptionalFeature optionalFeature) {
switch (optionalFeature) {
case STORE_BY_REFERENCE:
return true;
}
return false;
}
private URI getManagerUri(URI uri) {
return (uri == null) ? getDefaultURI() : uri;
}
private ClassLoader getManagerClassLoader(ClassLoader classLoader) {
return (classLoader == null) ? getDefaultClassLoader() : classLoader;
}
}