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/* * Copyright 2004 The Apache Software Foundation. * * Licensed 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 conf; import java.io.PrintWriter; import java.io.StringWriter; import java.sql.Connection; import java.sql.SQLException; import java.util.Iterator; import java.util.Properties; import org.apache.commons.dbcp.BasicDataSource; import org.apache.commons.dbcp.BasicDataSourceFactory; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.hibernate.HibernateException; import org.hibernate.cfg.Environment; import org.hibernate.connection.ConnectionProvider; import org.hibernate.connection.ConnectionProviderFactory; /** * <p>A connection provider that uses an Apache commons DBCP connection pool.</p> * * <p>To use this connection provider set:<br> * <code>hibernate.connection.provider_class org.hibernate.connection.DBCPConnectionProvider</code> * </p> * * <pre> * Supported Hibernate properties: * hibernate.connection.driver_class * hibernate.connection.url * hibernate.connection.username * hibernate.connection.password * hibernate.connection.isolation * hibernate.connection.autocommit * hibernate.connection.pool_size * hibernate.connection (JDBC driver properties) * </pre> * * <br> * All DBCP properties are also supported by using the hibernate.dbcp prefix. A * complete list can be found on the DBCP configuration page: <a * href="http://jakarta.apache.org/commons/dbcp/configuration.html" * >http://jakarta.apache.org/commons/dbcp/configuration.html</a>. <br> * * <pre> * Example: * hibernate.connection.provider_class org.hibernate.connection.DBCPConnectionProvider * hibernate.connection.driver_class org.hsqldb.jdbcDriver * hibernate.connection.username sa * hibernate.connection.password * hibernate.connection.url jdbc:hsqldb:test * hibernate.connection.pool_size 20 * hibernate.dbcp.initialSize 10 * hibernate.dbcp.maxWait 3000 * hibernate.dbcp.validationQuery select 1 from dual * </pre> * * <p> * More information about configuring/using DBCP can be found on the <a * href="http://jakarta.apache.org/commons/dbcp/">DBCP website</a>. There you * will also find the DBCP wiki, mailing lists, issue tracking and other support * facilities * </p> * * @see org.hibernate.connection.ConnectionProvider * @author Dirk Verbeeck */ public class DBCPConnectionProvider implements ConnectionProvider { private static final Log log = LogFactory.getLog(DBCPConnectionProvider.class); private static final String PREFIX = "hibernate.dbcp."; private BasicDataSource ds; // Old Environment property for backward-compatibility (property removed in Hibernate3) private static final String DBCP_PS_MAXACTIVE = "hibernate.dbcp.ps.maxActive"; // Property doesn't exists in Hibernate2 private static final String AUTOCOMMIT = "hibernate.connection.autocommit"; public void configure(Properties props) throws HibernateException { try { log.debug("Configure DBCPConnectionProvider"); // DBCP properties used to create the BasicDataSource Properties dbcpProperties = new Properties(); // DriverClass & url String jdbcDriverClass = props.getProperty(Environment.DRIVER); String jdbcUrl = props.getProperty(Environment.URL); dbcpProperties.put("driverClassName", jdbcDriverClass); dbcpProperties.put("url", jdbcUrl); // Username / password String username = props.getProperty(Environment.USER); String password = props.getProperty(Environment.PASS); dbcpProperties.put("username", username); dbcpProperties.put("password", password); // Isolation level String isolationLevel = props.getProperty(Environment.ISOLATION); if ((isolationLevel != null) && (isolationLevel.trim().length() > 0)) { dbcpProperties.put("defaultTransactionIsolation", isolationLevel); } // Turn off autocommit (unless autocommit property is set) String autocommit = props.getProperty(AUTOCOMMIT); if ((autocommit != null) && (autocommit.trim().length() > 0)) { dbcpProperties.put("defaultAutoCommit", autocommit); } else { dbcpProperties.put("defaultAutoCommit", String.valueOf(Boolean.FALSE)); } // Pool size String poolSize = props.getProperty(Environment.POOL_SIZE); if ((poolSize != null) && (poolSize.trim().length() > 0) && (Integer.parseInt(poolSize) > 0)) { dbcpProperties.put("maxActive", poolSize); } // Copy all "driver" properties into "connectionProperties" Properties driverProps = ConnectionProviderFactory.getConnectionProperties(props); if (driverProps.size() > 0) { StringBuffer connectionProperties = new StringBuffer(); for (Iterator iter = driverProps.keySet().iterator(); iter.hasNext();) { String key = (String) iter.next(); String value = driverProps.getProperty(key); connectionProperties.append(key).append('=').append(value); if (iter.hasNext()) { connectionProperties.append(';'); } } dbcpProperties.put("connectionProperties", connectionProperties.toString()); } // Copy all DBCP properties removing the prefix for (Iterator iter = props.keySet().iterator(); iter.hasNext();) { String key = String.valueOf(iter.next()); if (key.startsWith(PREFIX)) { String property = key.substring(PREFIX.length()); String value = props.getProperty(key); dbcpProperties.put(property, value); } } // Backward-compatibility if (props.getProperty(DBCP_PS_MAXACTIVE) != null) { dbcpProperties.put("poolPreparedStatements", String.valueOf(Boolean.TRUE)); dbcpProperties.put("maxOpenPreparedStatements", props.getProperty(DBCP_PS_MAXACTIVE)); } // Some debug info if (log.isDebugEnabled()) { log.debug("Creating a DBCP BasicDataSource with the following DBCP factory properties:"); StringWriter sw = new StringWriter(); dbcpProperties.list(new PrintWriter(sw, true)); log.debug(sw.toString()); } // Let the factory create the pool ds = (BasicDataSource) BasicDataSourceFactory.createDataSource(dbcpProperties); // The BasicDataSource has lazy initialization // borrowing a connection will start the DataSource // and make sure it is configured correctly. Connection conn = ds.getConnection(); conn.close(); // Log pool statistics before continuing. logStatistics(); } catch (Exception e) { String message = "Could not create a DBCP pool"; log.fatal(message, e); if (ds != null) { try { ds.close(); } catch (Exception e2) { // ignore } ds = null; } throw new HibernateException(message, e); } log.debug("Configure DBCPConnectionProvider complete"); } public Connection getConnection() throws SQLException { Connection conn = null; try { conn = ds.getConnection(); } finally { logStatistics(); } return conn; } public void closeConnection(Connection conn) throws SQLException { try { conn.close(); } finally { logStatistics(); } } public void close() throws HibernateException { log.debug("Close DBCPConnectionProvider"); logStatistics(); try { if (ds != null) { ds.close(); ds = null; } else { log.warn("Cannot close DBCP pool (not initialized)"); } } catch (Exception e) { throw new HibernateException("Could not close DBCP pool", e); } log.debug("Close DBCPConnectionProvider complete"); } protected void logStatistics() { if (log.isInfoEnabled()) { log.info("active: " + ds.getNumActive() + " (max: " + ds.getMaxActive() + ") " + "idle: " + ds.getNumIdle() + "(max: " + ds.getMaxIdle() + ")"); } } public boolean supportsAggressiveRelease() { // TODO Auto-generated method stub return false; } }