Java tutorial
/* * 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.hive.metastore.datasource; import org.apache.commons.dbcp.ConnectionFactory; import org.apache.commons.dbcp.DriverManagerConnectionFactory; import org.apache.commons.dbcp.PoolableConnectionFactory; import org.apache.commons.dbcp.PoolingDataSource; import org.apache.commons.pool.impl.GenericObjectPool; import org.apache.hadoop.conf.Configuration; import org.apache.hadoop.hive.metastore.conf.MetastoreConf; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import javax.sql.DataSource; import java.sql.SQLException; /** * DataSourceProvider for the dbcp connection pool. */ public class DbCPDataSourceProvider implements DataSourceProvider { private static final Logger LOG = LoggerFactory.getLogger(DbCPDataSourceProvider.class); static final String DBCP = "dbcp"; private static final String CONNECTION_TIMEOUT_PROPERTY = DBCP + ".maxWait"; private static final String CONNECTION_MAX_IDLE_PROPERTY = DBCP + ".maxIdle"; private static final String CONNECTION_MIN_IDLE_PROPERTY = DBCP + ".minIdle"; private static final String CONNECTION_TEST_BORROW_PROPERTY = DBCP + ".testOnBorrow"; private static final String CONNECTION_MIN_EVICT_MILLIS_PROPERTY = DBCP + ".minEvictableIdleTimeMillis"; private static final String CONNECTION_TEST_IDLEPROPERTY = DBCP + ".testWhileIdle"; private static final String CONNECTION_TIME_BETWEEN_EVICTION_RUNS_MILLIS = DBCP + ".timeBetweenEvictionRunsMillis"; private static final String CONNECTION_NUM_TESTS_PER_EVICTION_RUN = DBCP + ".numTestsPerEvictionRun"; private static final String CONNECTION_TEST_ON_RETURN = DBCP + ".testOnReturn"; private static final String CONNECTION_SOFT_MIN_EVICTABLE_IDLE_TIME = DBCP + ".softMinEvictableIdleTimeMillis"; private static final String CONNECTION_LIFO = DBCP + ".lifo"; @Override public DataSource create(Configuration hdpConfig) throws SQLException { LOG.debug("Creating dbcp connection pool for the MetaStore"); String driverUrl = DataSourceProvider.getMetastoreJdbcDriverUrl(hdpConfig); String user = DataSourceProvider.getMetastoreJdbcUser(hdpConfig); String passwd = DataSourceProvider.getMetastoreJdbcPasswd(hdpConfig); int maxPoolSize = hdpConfig.getInt(MetastoreConf.ConfVars.CONNECTION_POOLING_MAX_CONNECTIONS.getVarname(), ((Long) MetastoreConf.ConfVars.CONNECTION_POOLING_MAX_CONNECTIONS.getDefaultVal()).intValue()); long connectionTimeout = hdpConfig.getLong(CONNECTION_TIMEOUT_PROPERTY, 30000L); int connectionMaxIlde = hdpConfig.getInt(CONNECTION_MAX_IDLE_PROPERTY, GenericObjectPool.DEFAULT_MAX_IDLE); int connectionMinIlde = hdpConfig.getInt(CONNECTION_MIN_IDLE_PROPERTY, GenericObjectPool.DEFAULT_MIN_IDLE); boolean testOnBorrow = hdpConfig.getBoolean(CONNECTION_TEST_BORROW_PROPERTY, GenericObjectPool.DEFAULT_TEST_ON_BORROW); long evictionTimeMillis = hdpConfig.getLong(CONNECTION_MIN_EVICT_MILLIS_PROPERTY, GenericObjectPool.DEFAULT_MIN_EVICTABLE_IDLE_TIME_MILLIS); boolean testWhileIdle = hdpConfig.getBoolean(CONNECTION_TEST_IDLEPROPERTY, GenericObjectPool.DEFAULT_TEST_WHILE_IDLE); long timeBetweenEvictionRuns = hdpConfig.getLong(CONNECTION_TIME_BETWEEN_EVICTION_RUNS_MILLIS, GenericObjectPool.DEFAULT_TIME_BETWEEN_EVICTION_RUNS_MILLIS); int numTestsPerEvictionRun = hdpConfig.getInt(CONNECTION_NUM_TESTS_PER_EVICTION_RUN, GenericObjectPool.DEFAULT_NUM_TESTS_PER_EVICTION_RUN); boolean testOnReturn = hdpConfig.getBoolean(CONNECTION_TEST_ON_RETURN, GenericObjectPool.DEFAULT_TEST_ON_RETURN); long softMinEvictableIdleTimeMillis = hdpConfig.getLong(CONNECTION_SOFT_MIN_EVICTABLE_IDLE_TIME, GenericObjectPool.DEFAULT_SOFT_MIN_EVICTABLE_IDLE_TIME_MILLIS); boolean lifo = hdpConfig.getBoolean(CONNECTION_LIFO, GenericObjectPool.DEFAULT_LIFO); GenericObjectPool objectPool = new GenericObjectPool(); objectPool.setMaxActive(maxPoolSize); objectPool.setMaxWait(connectionTimeout); objectPool.setMaxIdle(connectionMaxIlde); objectPool.setMinIdle(connectionMinIlde); objectPool.setTestOnBorrow(testOnBorrow); objectPool.setTestWhileIdle(testWhileIdle); objectPool.setMinEvictableIdleTimeMillis(evictionTimeMillis); objectPool.setTimeBetweenEvictionRunsMillis(timeBetweenEvictionRuns); objectPool.setNumTestsPerEvictionRun(numTestsPerEvictionRun); objectPool.setTestOnReturn(testOnReturn); objectPool.setSoftMinEvictableIdleTimeMillis(softMinEvictableIdleTimeMillis); objectPool.setLifo(lifo); ConnectionFactory connFactory = new DriverManagerConnectionFactory(driverUrl, user, passwd); // This doesn't get used, but it's still necessary, see // https://git1-us-west.apache.org/repos/asf?p=commons-dbcp.git;a=blob;f=doc/ManualPoolingDataSourceExample.java; // h=f45af2b8481f030b27364e505984c0eef4f35cdb;hb=refs/heads/DBCP_1_5_x_BRANCH new PoolableConnectionFactory(connFactory, objectPool, null, null, false, true); return new PoolingDataSource(objectPool); } @Override public boolean mayReturnClosedConnection() { // Only BoneCP should return true return false; } @Override public boolean supports(Configuration configuration) { String poolingType = MetastoreConf.getVar(configuration, MetastoreConf.ConfVars.CONNECTION_POOLING_TYPE); return DBCP.equalsIgnoreCase(poolingType); } }