/* * 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 org.apache.jena.atlas.iterator.Iter ; import org.apache.jena.atlas.lib.Cache ; /** A cache that keeps nothing */ public final class Cache0<K, V> implements Cache<K, V> { @Override public boolean containsKey(K key) { return false ; } @Override public V getIfPresent(K key) { return null ; } @Override public V getOrFill(K key, Callable<V> callable) { return null ; } @Override public void put(K key, V thing) {} @Override public void remove(K key) {} @Override public Iterator<K> keys() { return Iter.nullIterator() ; } @Override public boolean isEmpty() { return true ; } @Override public void clear() {} @Override public long size() { return 0 ; } @Override public void setDropHandler(BiConsumer<K, V> dropHandler) {} }