| /** |
| * 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.jena.atlas.lib.cache; |
| |
| import java.util.Iterator ; |
| import java.util.concurrent.Callable ; |
| import java.util.function.BiConsumer ; |
| import java.util.function.Function; |
| |
| import com.github.benmanes.caffeine.cache.Caffeine; |
| import com.github.benmanes.caffeine.cache.RemovalListener; |
| |
| import org.apache.jena.atlas.lib.Cache ; |
| import org.apache.jena.atlas.logging.Log ; |
| |
| /** Wrapper around a com.github.benmanes.caffeine */ |
| final public class CacheCaffeine<K,V> implements Cache<K, V> |
| { |
| private static boolean WITH_STATS = false; |
| private BiConsumer<K, V> dropHandler = null ; |
| |
| private com.github.benmanes.caffeine.cache.Cache<K,V> cache ; |
| // cache size specified on creation. |
| private final int size; |
| |
| public CacheCaffeine(int size) { |
| this(size, null); |
| } |
| |
| public CacheCaffeine(int size, BiConsumer<K, V> dropHandler) { |
| @SuppressWarnings("unchecked") |
| Caffeine<K,V> builder = (Caffeine<K,V>)Caffeine.newBuilder() |
| .maximumSize(size) |
| .initialCapacity(size/4) |
| // Eviction immediately using the caller thread. |
| .executor(c->c.run()); |
| |
| if ( dropHandler != null ) { |
| RemovalListener<K,V> drop = (key, value, cause)-> { |
| if ( dropHandler != null ) |
| dropHandler.accept(key, value); |
| }; |
| builder = builder.removalListener(drop); |
| } |
| if ( WITH_STATS ) |
| builder = builder.recordStats(); |
| cache = builder.build(); |
| this.size = size; |
| } |
| |
| public CacheCaffeine(com.github.benmanes.caffeine.cache.Cache<K,V> caffeine) { |
| cache = caffeine; |
| this.size = -1; // Unknown |
| } |
| |
| // Callable to function conversion. |
| private static <X> X call(Callable<X> filler) { |
| try { |
| return filler.call(); |
| } catch (Exception e) { |
| Log.warn(CacheCaffeine.class, "Execution exception filling cache", e) ; |
| return null ; |
| } |
| } |
| |
| @Override |
| public V get(K key, Function<K, V> f) { |
| return cache.get(key, f); |
| } |
| |
| @Override |
| public V getIfPresent(K key) { |
| return cache.getIfPresent(key) ; |
| } |
| |
| @Override |
| public void put(K key, V thing) { |
| if (thing == null) |
| cache.invalidate(key); |
| else |
| cache.put(key, thing); |
| } |
| |
| @Override |
| public boolean containsKey(K key) { |
| return cache.getIfPresent(key) != null ; |
| } |
| |
| @Override |
| public void remove(K key) { |
| cache.invalidate(key) ; |
| } |
| |
| @Override |
| public Iterator<K> keys() { |
| return cache.asMap().keySet().iterator() ; |
| } |
| |
| @Override |
| public boolean isEmpty() { |
| return cache.estimatedSize() == 0 ; |
| } |
| |
| @Override |
| public void clear() { |
| cache.invalidateAll() ; |
| } |
| |
| @Override |
| public long size() { |
| return cache.estimatedSize() ; |
| } |
| |
| /** |
| * Forces the cache to clean up stale entries |
| */ |
| public void cleanUp() { |
| this.cache.cleanUp(); |
| } |
| } |
| |