datasourceconnectionprovider.java

用Java实现的23个常用设计模式源代码

//$Id: DatasourceConnectionProvider.java,v 1.8.2.2 2003/10/25 11:11:45 oneovthafew Exp $
package net.sf.hibernate.connection;

import java.sql.Connection;
import java.sql.SQLException;
import java.util.Properties;

import javax.sql.DataSource;

import net.sf.hibernate.HibernateException;
import net.sf.hibernate.cfg.Environment;
import net.sf.hibernate.util.NamingHelper;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

/**
 * A connection provider that uses a <tt>DataSource</tt> registered with JNDI.
 * Hibernate will use this <tt>ConnectionProvider</tt> by default if the
 * property <tt>hibernate.connection.datasource</tt> is set.
 * @see ConnectionProvider
 * @author Gavin King
 */
public class DatasourceConnectionProvider implements ConnectionProvider {
	private DataSource ds;
	private String user;
	private String pass;
	
	private static final Log log = LogFactory.getLog(DatasourceConnectionProvider.class);
	
	public void configure(Properties props) throws HibernateException {
		
		String jndiName = props.getProperty(Environment.DATASOURCE);
		if (jndiName==null) {
			String msg = "datasource JNDI name was not specified by property " + Environment.DATASOURCE;
			log.fatal(msg);
			throw new HibernateException(msg);
		}
		
		user = props.getProperty(Environment.USER);
		pass = props.getProperty(Environment.PASS);
		
		try {
			ds = (DataSource) NamingHelper.getInitialContext(props).lookup(jndiName);
		}
		catch (Exception e) {
			log.fatal( "Could not find datasource: " + jndiName, e );
			throw new HibernateException( "Could not find datasource", e );
		}
		if (ds==null) throw new HibernateException( "Could not find datasource: " + jndiName );
		log.info( "Using datasource: " + jndiName );
	}
	
	public Connection getConnection() throws SQLException {
		if (user != null || pass != null) {
			return ds.getConnection(user, pass);
		}
		else {
			return ds.getConnection();
		}
	}
	
	public void closeConnection(Connection conn) throws SQLException {
		conn.close();
	}
	
	public void close() {}

}