sharedpooldatasourcefactory.java

另外一种持久性o/m软件

package org.apache.torque.dsfactory;

/*
 * Copyright 2001-2004 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.
 */

import javax.sql.ConnectionPoolDataSource;
import javax.sql.DataSource;

import org.apache.commons.configuration.Configuration;

import org.apache.commons.dbcp.datasources.SharedPoolDataSource;

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

import org.apache.torque.Torque;
import org.apache.torque.TorqueException;

/**
 * A factory that looks up the DataSource using the JDBC2 pool methods.
 *
 * @author <a href="mailto:[e-mail]">John McNally</a>
 * @author <a href="mailto:[e-mail]">Henning P. Schmiedehausen</a>
 * @version $Id: SharedPoolDataSourceFactory.java,v 1.4 2005/07/02 07:22:33 tfischer Exp $
 */
public class SharedPoolDataSourceFactory
    extends AbstractDataSourceFactory
    implements DataSourceFactory
{

    /** The log. */
    private static Log log 
            = LogFactory.getLog(SharedPoolDataSourceFactory.class);

    /** The wrapped <code>DataSource</code>. */
    private SharedPoolDataSource ds;

    /**
     * @see org.apache.torque.dsfactory.DataSourceFactory#getDataSource
     */
    public DataSource getDataSource()
    {
        return ds;
    }

    /**
     * @see org.apache.torque.dsfactory.DataSourceFactory#initialize
     */
    public void initialize(Configuration configuration) throws TorqueException
    {
        super.initialize(configuration);

        ConnectionPoolDataSource cpds = initCPDS(configuration);
        SharedPoolDataSource ds = initJdbc2Pool(configuration);
        ds.setConnectionPoolDataSource(cpds);
        this.ds = ds;
    }

    /**
     * Initializes the Jdbc2PoolDataSource.
     *
     * @param configuration where to read the settings from
     * @throws TorqueException if a property set fails
     * @return a configured <code>Jdbc2PoolDataSource</code>
     */
    private SharedPoolDataSource initJdbc2Pool(Configuration configuration)
        throws TorqueException
    {
        log.debug("Starting initJdbc2Pool");
        SharedPoolDataSource ds = new SharedPoolDataSource();
        Configuration c = Torque.getConfiguration();

        if (c == null || c.isEmpty())
        {
            log.warn("Global Configuration not set,"
                    + " no Default pool data source configured!");
        }
        else
        {
            Configuration conf = c.subset(DEFAULT_POOL_KEY);
            applyConfiguration(conf, ds);
        }

        Configuration conf = configuration.subset(POOL_KEY);
        applyConfiguration(conf, ds);
        return ds;
    }
    
    
    /**
     * Closes the pool associated with this factory and releases it.
     * @throws TorqueException if the pool cannot be closed properly
     */
    public void close() throws TorqueException
    {
        try 
        {
        	ds.close();
        }
        catch (Exception e)
        {
            log.error("Exception caught during close()", e);
            throw new TorqueException(e);
        }
        ds = null;
    }
}