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/********************************************************************************** * $URL: $ * $Id: SakaiBasicDataSource.java 105077 2012-02-24 22:54:29Z ottenhoff@longsight.com $ *********************************************************************************** * * Copyright (c) 2005, 2006, 2008 Sakai Foundation * * Licensed under the Educational Community 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.opensource.org/licenses/ECL-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.sakaiproject.tomcat.jdbc.pool; import java.lang.management.ManagementFactory; import java.sql.Connection; import java.sql.Driver; import java.sql.DriverManager; import java.sql.SQLException; import java.util.Properties; import javax.management.InstanceAlreadyExistsException; import javax.management.MBeanRegistrationException; import javax.management.MBeanServer; import javax.management.MalformedObjectNameException; import javax.management.NotCompliantMBeanException; import javax.management.ObjectName; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.apache.tomcat.jdbc.pool.DataSource; import org.apache.tomcat.jdbc.pool.DataSourceFactory; import org.apache.tomcat.jdbc.pool.PoolProperties; /** * <p> * SakaiBasicDataSource extends apache tomcat's DataSource ... * </p> */ public class SakaiBasicDataSource extends DataSource { /** Our logger. */ private static Log M_log = LogFactory.getLog(SakaiBasicDataSource.class); private MBeanServer mBeanServer = ManagementFactory.getPlatformMBeanServer(); /** Configuration: to rollback each connection when returned to the pool. */ protected boolean m_rollbackOnReturn = false; //Needed for DBCP compat private boolean poolPreparedStatements; private int maxOpenPreparedStatements; public MBeanServer getMBeanServer() { return mBeanServer; } public void setMaxOpenPreparedStatements(int maxOpenPreparedStatements) { M_log.info("MaxOpenPreparedStatments not used"); this.maxOpenPreparedStatements = maxOpenPreparedStatements; } public void setPoolPreparedStatements(boolean poolPreparedStatements) { M_log.info("PoolPreparedStatements not used"); this.poolPreparedStatements = poolPreparedStatements; } /** * Set the default transaction isolation level from a string value, based on the settings and values in java.sql.Connection * * @param defaultTransactionIsolation */ public void setDefaultTransactionIsolationString(String defaultTransactionIsolation) { if ((defaultTransactionIsolation == null) || (defaultTransactionIsolation.trim().length() == 0)) { setDefaultTransactionIsolation(DataSourceFactory.UNKNOWN_TRANSACTIONISOLATION); } else if (defaultTransactionIsolation.trim().equalsIgnoreCase("TRANSACTION_NONE")) { setDefaultTransactionIsolation(Connection.TRANSACTION_NONE); } else if (defaultTransactionIsolation.trim().equalsIgnoreCase("TRANSACTION_READ_UNCOMMITTED")) { setDefaultTransactionIsolation(Connection.TRANSACTION_READ_UNCOMMITTED); } else if (defaultTransactionIsolation.trim().equalsIgnoreCase("TRANSACTION_READ_COMMITTED")) { setDefaultTransactionIsolation(Connection.TRANSACTION_READ_COMMITTED); } else if (defaultTransactionIsolation.trim().equalsIgnoreCase("TRANSACTION_REPEATABLE_READ")) { setDefaultTransactionIsolation(Connection.TRANSACTION_REPEATABLE_READ); } else if (defaultTransactionIsolation.trim().equalsIgnoreCase("TRANSACTION_SERIALIZABLE")) { setDefaultTransactionIsolation(Connection.TRANSACTION_SERIALIZABLE); } else { setDefaultTransactionIsolation(DataSourceFactory.UNKNOWN_TRANSACTIONISOLATION); M_log.warn("invalid transaction isolation level: " + defaultTransactionIsolation); } } /** * Set the rollback on borrow configuration. * * @param value * if true, rollback each connection when borrowed from the pool, if false, do not. */ public synchronized void setRollbackOnBorrow(boolean value) { m_rollbackOnReturn = value; } /** * @exception SQLException * if the object pool cannot be created. */ protected void init() throws MalformedObjectNameException, MBeanRegistrationException, NotCompliantMBeanException, SQLException, InstanceAlreadyExistsException { M_log.info("init()"); // Load the JDBC driver class PoolProperties connectionPool = (PoolProperties) createPool().getPoolProperties(); String driverClassName = getDriverClassName(); //Validate the class if (driverClassName != null) { try { Class.forName(driverClassName); } catch (Throwable t) { String message = "Cannot load JDBC driver class '" + driverClassName + "'"; M_log.error(message, t); throw new SQLException(message, t); } } // Can't test without a validationQuery if (getValidationQuery() == null) { connectionPool.setTestOnBorrow(false); connectionPool.setTestOnReturn(false); connectionPool.setTestWhileIdle(false); } // Set up statement pool, if desired // What did this do?? /* GenericKeyedObjectPoolFactory statementPoolFactory = null; if (isPoolPreparedStatements()) { statementPoolFactory = new GenericKeyedObjectPoolFactory(null, -1, // unlimited maxActive (per key) GenericKeyedObjectPool.WHEN_EXHAUSTED_FAIL, 0, // maxWait 1, // maxIdle (per key) maxOpenPreparedStatements); } */ // Set up the driver connection factory we will use if (getUsername() == null) { M_log.warn("Tomcat DataSource configured without a 'username'"); } String password = createPool().getPoolProperties().getUsername(); if (password == null) { M_log.warn("Tomcat DataSource configured without a 'password'"); } setPoolProperties(connectionPool); // Register an MBean so that we can view statistics on the pool via JMX ObjectName on = new ObjectName("TomcatJDBC:type=statistics,application=TomcatJDBCSakaiPool"); if (!mBeanServer.isRegistered(on)) { M_log.info("Registering Tomcat JDBC pool with JMX " + mBeanServer); mBeanServer.registerMBean(getPool().getJmxPool(), on); } //Does it need any of this?? /* DriverConnectionFactory driverConnectionFactory = new DriverConnectionFactory(driver, url, connectionProperties); // Set up the poolable connection factory we will use PoolableConnectionFactory connectionFactory = null; try { connectionFactory = new SakaiPoolableConnectionFactory(driverConnectionFactory, connectionPool, statementPoolFactory, validationQuery, defaultReadOnly, defaultAutoCommit, defaultTransactionIsolation, defaultCatalog, ,null, m_rollbackOnReturn); if (connectionFactory == null) { throw new SQLException("Cannot create PoolableConnectionFactory"); } // Sakai: validateConnectionFactory(connectionFactory); } catch (RuntimeException e) { throw e; } catch (Exception e) { throw new SQLException("Cannot create PoolableConnectionFactory (" + e.getMessage() + ")", e); } // Create and return the pooling data source to manage the connections dataSource = new PoolingDataSource(connectionPool); ((PoolingDataSource) dataSource).setAccessToUnderlyingConnectionAllowed(isAccessToUnderlyingConnectionAllowed()); dataSource.setLogWriter(logWriter); try { for (int i = 0; i < initialSize; i++) { connectionPool.addObject(); } } catch (Exception e) { throw new SQLException("Error preloading the connection pool", e); } */ } }