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.commons.dbcp.managed; import org.apache.commons.dbcp.AbandonedConfig; import org.apache.commons.dbcp.BasicDataSource; import org.apache.commons.dbcp.ConnectionFactory; import org.apache.commons.dbcp.PoolableConnectionFactory; import org.apache.commons.dbcp.PoolingDataSource; import org.apache.commons.pool.KeyedObjectPoolFactory; import javax.sql.XADataSource; import javax.transaction.TransactionManager; import java.sql.SQLException; /** * <p>BasicManagedDataSource is an extension of BasicDataSource which * creates ManagedConnections. This data source can create either * full two-phase-commit XA connections or one-phase-commit * local connections. Both types of connections are committed or * rolled back as part of the global transaction (a.k.a. XA * transaction or JTA Transaction), but only XA connections can be * recovered in the case of a system crash. * </p> * <p>BasicManagedDataSource adds the TransactionManager and XADataSource * properties. The TransactionManager property is required and is * used to elist connections in global transactions. The XADataSource * is optional and if set is the class name of the XADataSource class * for a two-phase-commit JDBC driver. If the XADataSource property * is set, the driverClassName is ignored and a DataSourceXAConnectionFactory * is created. Otherwise, a standard DriverConnectionFactory is created * and wrapped with a LocalXAConnectionFactory. * </p> * * @see BasicDataSource * @see ManagedConnection * @version $Revision$ */ public class BasicManagedDataSource extends BasicDataSource { /** Transaction Registry */ private TransactionRegistry transactionRegistry; /** Transaction Manager */ private transient TransactionManager transactionManager; /** XA datasource class name */ private String xaDataSource; /** XA datasource instance */ private XADataSource xaDataSourceInstance; /** * Gets the XADataSource instance used by the XAConnectionFactory. * * @return the XADataSource */ public synchronized XADataSource getXaDataSourceInstance() { return xaDataSourceInstance; } /** * <p>Sets the XADataSource instance used by the XAConnectionFactory.</p> * <p> * Note: this method currently has no effect once the pool has been * initialized. The pool is initialized the first time one of the * following methods is invoked: <code>getConnection, setLogwriter, * setLoginTimeout, getLoginTimeout, getLogWriter.</code></p> * * @param xaDataSourceInstance XADataSource instance */ public synchronized void setXaDataSourceInstance(XADataSource xaDataSourceInstance) { this.xaDataSourceInstance = xaDataSourceInstance; xaDataSource = xaDataSourceInstance == null ? null : xaDataSourceInstance.getClass().getName(); } /** * Gets the required transaction manager property. * @return the transaction manager used to enlist connections */ public TransactionManager getTransactionManager() { return transactionManager; } /** * Gets the transaction registry. * @return the transaction registry associating XAResources with managed connections */ protected synchronized TransactionRegistry getTransactionRegistry() { return transactionRegistry; } /** * Sets the required transaction manager property. * @param transactionManager the transaction manager used to enlist connections */ public void setTransactionManager(TransactionManager transactionManager) { this.transactionManager = transactionManager; } /** * Gets the optional XADataSource class name. * @return the optional XADataSource class name */ public synchronized String getXADataSource() { return xaDataSource; } /** * Sets the optional XADataSource class name. * @param xaDataSource the optional XADataSource class name */ public synchronized void setXADataSource(String xaDataSource) { this.xaDataSource = xaDataSource; } protected ConnectionFactory createConnectionFactory() throws SQLException { if (transactionManager == null) { throw new SQLException("Transaction manager must be set before a connection can be created"); } // If xa data source is not specified a DriverConnectionFactory is created and wrapped with a LocalXAConnectionFactory if (xaDataSource == null) { ConnectionFactory connectionFactory = super.createConnectionFactory(); XAConnectionFactory xaConnectionFactory = new LocalXAConnectionFactory(getTransactionManager(), connectionFactory); transactionRegistry = xaConnectionFactory.getTransactionRegistry(); return xaConnectionFactory; } // Create the XADataSource instance using the configured class name if it has not been set if (xaDataSourceInstance == null) { Class xaDataSourceClass = null; try { xaDataSourceClass = Class.forName(xaDataSource); } catch (Throwable t) { String message = "Cannot load XA data source class '" + xaDataSource + "'"; throw (SQLException) new SQLException(message).initCause(t); } try { xaDataSourceInstance = (XADataSource) xaDataSourceClass.newInstance(); } catch (Throwable t) { String message = "Cannot create XA data source of class '" + xaDataSource + "'"; throw (SQLException) new SQLException(message).initCause(t); } } // finally, create the XAConectionFactory using the XA data source XAConnectionFactory xaConnectionFactory = new DataSourceXAConnectionFactory(getTransactionManager(), xaDataSourceInstance, username, password); transactionRegistry = xaConnectionFactory.getTransactionRegistry(); return xaConnectionFactory; } protected void createDataSourceInstance() throws SQLException { PoolingDataSource pds = new ManagedDataSource(connectionPool, transactionRegistry); pds.setAccessToUnderlyingConnectionAllowed(isAccessToUnderlyingConnectionAllowed()); pds.setLogWriter(logWriter); dataSource = pds; } /** * Creates the PoolableConnectionFactory and attaches it to the connection pool. * * @param driverConnectionFactory JDBC connection factory created by {@link #createConnectionFactory()} * @param statementPoolFactory statement pool factory (null if statement pooling is turned off) * @param abandonedConfig abandoned connection tracking configuration (null if no tracking) * @throws SQLException if an error occurs creating the PoolableConnectionFactory */ protected void createPoolableConnectionFactory(ConnectionFactory driverConnectionFactory, KeyedObjectPoolFactory statementPoolFactory, AbandonedConfig abandonedConfig) throws SQLException { PoolableConnectionFactory connectionFactory = null; try { connectionFactory = new PoolableManagedConnectionFactory((XAConnectionFactory) driverConnectionFactory, connectionPool, statementPoolFactory, validationQuery, validationQueryTimeout, connectionInitSqls, defaultReadOnly, defaultAutoCommit, defaultTransactionIsolation, defaultCatalog, abandonedConfig); validateConnectionFactory(connectionFactory); } catch (RuntimeException e) { throw e; } catch (Exception e) { throw (SQLException) new SQLException( "Cannot create PoolableConnectionFactory (" + e.getMessage() + ")").initCause(e); } } }