| /* |
| * 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.drill.exec.coord.store; |
| |
| import java.util.List; |
| import java.util.Map; |
| |
| import com.google.common.base.Preconditions; |
| import com.google.common.collect.Lists; |
| import com.google.common.collect.Maps; |
| import org.apache.drill.common.AutoCloseables; |
| |
| public class CachingTransientStoreFactory implements TransientStoreFactory { |
| private final TransientStoreFactory delegate; |
| private final Map<TransientStoreConfig, TransientStore> cache = Maps.newHashMap(); |
| |
| public CachingTransientStoreFactory(final TransientStoreFactory delegate) { |
| this.delegate = Preconditions.checkNotNull(delegate, "delegate factory is required"); |
| } |
| |
| @Override |
| public <V> TransientStore<V> getOrCreateStore(final TransientStoreConfig<V> config) { |
| final TransientStore<V> store = cache.get(Preconditions.checkNotNull(config, "config is required")); |
| if (store != null) { |
| return store; |
| } |
| |
| final TransientStore<V> newStore = delegate.getOrCreateStore(config); |
| cache.put(config, newStore); |
| return newStore; |
| } |
| |
| @Override |
| public void close() throws Exception { |
| final List<AutoCloseable> closeables = Lists.newArrayList(); |
| for(final AutoCloseable store : cache.values()){ |
| closeables.add(store); |
| } |
| closeables.add(delegate); |
| cache.clear(); |
| AutoCloseables.close(closeables); |
| } |
| |
| public static TransientStoreFactory of(final TransientStoreFactory delegate) { |
| return new CachingTransientStoreFactory(delegate); |
| } |
| } |