| /** |
| * |
| * 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.hadoop.hbase.regionserver; |
| |
| import java.io.IOException; |
| import java.util.List; |
| |
| import org.apache.hadoop.conf.Configuration; |
| import org.apache.hadoop.hbase.CellComparator; |
| import org.apache.hadoop.hbase.regionserver.compactions.CompactionContext; |
| import org.apache.hadoop.hbase.regionserver.compactions.CompactionPolicy; |
| import org.apache.hadoop.hbase.regionserver.compactions.Compactor; |
| import org.apache.hadoop.hbase.util.ReflectionUtils; |
| import org.apache.yetus.audience.InterfaceAudience; |
| |
| /** |
| * StoreEngine is a factory that can create the objects necessary for HStore to operate. |
| * Since not all compaction policies, compactors and store file managers are compatible, |
| * they are tied together and replaced together via StoreEngine-s. |
| */ |
| @InterfaceAudience.Private |
| public abstract class StoreEngine<SF extends StoreFlusher, |
| CP extends CompactionPolicy, C extends Compactor, SFM extends StoreFileManager> { |
| protected SF storeFlusher; |
| protected CP compactionPolicy; |
| protected C compactor; |
| protected SFM storeFileManager; |
| |
| /** |
| * The name of the configuration parameter that specifies the class of |
| * a store engine that is used to manage and compact HBase store files. |
| */ |
| public static final String STORE_ENGINE_CLASS_KEY = "hbase.hstore.engine.class"; |
| |
| private static final Class<? extends StoreEngine<?, ?, ?, ?>> |
| DEFAULT_STORE_ENGINE_CLASS = DefaultStoreEngine.class; |
| |
| /** |
| * @return Compaction policy to use. |
| */ |
| public CompactionPolicy getCompactionPolicy() { |
| return this.compactionPolicy; |
| } |
| |
| /** |
| * @return Compactor to use. |
| */ |
| public Compactor getCompactor() { |
| return this.compactor; |
| } |
| |
| /** |
| * @return Store file manager to use. |
| */ |
| public StoreFileManager getStoreFileManager() { |
| return this.storeFileManager; |
| } |
| |
| /** |
| * @return Store flusher to use. |
| */ |
| public StoreFlusher getStoreFlusher() { |
| return this.storeFlusher; |
| } |
| |
| /** |
| * @param filesCompacting Files currently compacting |
| * @return whether a compaction selection is possible |
| */ |
| public abstract boolean needsCompaction(List<HStoreFile> filesCompacting); |
| |
| /** |
| * Creates an instance of a compaction context specific to this engine. |
| * Doesn't actually select or start a compaction. See CompactionContext class comment. |
| * @return New CompactionContext object. |
| */ |
| public abstract CompactionContext createCompaction() throws IOException; |
| |
| /** |
| * Create the StoreEngine's components. |
| */ |
| protected abstract void createComponents( |
| Configuration conf, HStore store, CellComparator cellComparator) throws IOException; |
| |
| private void createComponentsOnce( |
| Configuration conf, HStore store, CellComparator cellComparator) throws IOException { |
| assert compactor == null && compactionPolicy == null |
| && storeFileManager == null && storeFlusher == null; |
| createComponents(conf, store, cellComparator); |
| assert compactor != null && compactionPolicy != null |
| && storeFileManager != null && storeFlusher != null; |
| } |
| |
| /** |
| * Create the StoreEngine configured for the given Store. |
| * @param store The store. An unfortunate dependency needed due to it |
| * being passed to coprocessors via the compactor. |
| * @param conf Store configuration. |
| * @param cellComparator CellComparator for storeFileManager. |
| * @return StoreEngine to use. |
| */ |
| public static StoreEngine<?, ?, ?, ?> create( |
| HStore store, Configuration conf, CellComparator cellComparator) throws IOException { |
| String className = conf.get(STORE_ENGINE_CLASS_KEY, DEFAULT_STORE_ENGINE_CLASS.getName()); |
| try { |
| StoreEngine<?,?,?,?> se = ReflectionUtils.instantiateWithCustomCtor( |
| className, new Class[] { }, new Object[] { }); |
| se.createComponentsOnce(conf, store, cellComparator); |
| return se; |
| } catch (Exception e) { |
| throw new IOException("Unable to load configured store engine '" + className + "'", e); |
| } |
| } |
| } |