| /* |
| * 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.store.hbase; |
| |
| import static org.apache.drill.shaded.guava.com.google.common.base.Preconditions.checkNotNull; |
| |
| import java.util.concurrent.ExecutionException; |
| import java.util.concurrent.TimeUnit; |
| |
| import org.apache.drill.common.exceptions.UserException; |
| import org.apache.drill.exec.store.hbase.HBaseStoragePlugin.HBaseConnectionKey; |
| import org.apache.hadoop.hbase.client.Connection; |
| import org.apache.hadoop.hbase.client.ConnectionFactory; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| import org.apache.drill.shaded.guava.com.google.common.cache.CacheBuilder; |
| import org.apache.drill.shaded.guava.com.google.common.cache.CacheLoader; |
| import org.apache.drill.shaded.guava.com.google.common.cache.LoadingCache; |
| import org.apache.drill.shaded.guava.com.google.common.cache.RemovalListener; |
| import org.apache.drill.shaded.guava.com.google.common.cache.RemovalNotification; |
| import org.apache.drill.shaded.guava.com.google.common.util.concurrent.UncheckedExecutionException; |
| |
| /** |
| * <p>A singleton class which manages the lifecycle of HBase connections.</p> |
| * <p>One connection per storage plugin instance is maintained.</p> |
| */ |
| public final class HBaseConnectionManager |
| extends CacheLoader<HBaseConnectionKey, Connection> implements RemovalListener<HBaseConnectionKey, Connection> { |
| private static final Logger logger = LoggerFactory.getLogger(HBaseConnectionManager.class); |
| |
| public static final HBaseConnectionManager INSTANCE = new HBaseConnectionManager(); |
| |
| private final LoadingCache<HBaseConnectionKey, Connection> connectionCache; |
| |
| private HBaseConnectionManager() { |
| this.connectionCache = CacheBuilder.newBuilder() |
| .expireAfterAccess(1, TimeUnit.HOURS) // Connections will be closed after 1 hour of inactivity |
| .removalListener(this) |
| .build(this); |
| } |
| |
| private boolean isValid(Connection conn) { |
| return conn != null |
| && !conn.isAborted() |
| && !conn.isClosed(); |
| } |
| |
| @Override |
| public Connection load(HBaseConnectionKey key) throws Exception { |
| Connection connection = ConnectionFactory.createConnection(key.getHBaseConf()); |
| logger.info("HBase connection '{}' created.", connection); |
| return connection; |
| } |
| |
| @Override |
| public void onRemoval(RemovalNotification<HBaseConnectionKey, Connection> notification) { |
| try { |
| Connection conn = notification.getValue(); |
| if (isValid(conn)) { |
| conn.close(); |
| } |
| logger.info("HBase connection '{}' closed.", conn); |
| } catch (Throwable t) { |
| logger.warn("Error while closing HBase connection.", t); |
| } |
| } |
| |
| public Connection getConnection(HBaseConnectionKey key) { |
| checkNotNull(key); |
| try { |
| Connection conn = connectionCache.get(key); |
| if (!isValid(conn)) { |
| key.lock(); // invalidate the connection with a per storage plugin lock |
| try { |
| conn = connectionCache.get(key); |
| if (!isValid(conn)) { |
| connectionCache.invalidate(key); |
| conn = connectionCache.get(key); |
| } |
| } finally { |
| key.unlock(); |
| } |
| } |
| return conn; |
| } catch (ExecutionException | UncheckedExecutionException e) { |
| throw UserException.dataReadError(e.getCause()).build(logger); |
| } |
| } |
| |
| public void closeConnection(HBaseConnectionKey key) { |
| checkNotNull(key); |
| connectionCache.invalidate(key); |
| } |
| |
| } |