hermes.store.jdbc.JDBCConnectionPool.java Source code

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Here is the source code for hermes.store.jdbc.JDBCConnectionPool.java

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/* 
 * Copyright 2003,2004,2005 Colin Crist
 *
 * 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 hermes.store.jdbc;

import hermes.HermesException;
import hermes.impl.pool.ObjectPool;
import hermes.impl.pool.ObjectPoolProxy;

import java.lang.reflect.Proxy;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;

import org.apache.commons.dbutils.DbUtils;
import org.apache.log4j.Logger;

/**
 * A connection pool for JDBC connections.
 * 
 * @author colincrist@hermesjms.com
 * @version $Id: JDBCConnectionPool.java,v 1.4 2005/12/14 08:11:25 colincrist Exp $
 */

public class JDBCConnectionPool extends ObjectPool<Connection> {
    private static final Logger log = Logger.getLogger(JDBCConnectionPool.class);
    private String url;
    private boolean autoCommit;

    public JDBCConnectionPool(String url, int poolSize, boolean autoCommit) {
        super(poolSize);

        this.url = url;
        this.autoCommit = autoCommit;
    }

    protected Connection makeObject() throws HermesException {
        try {
            Connection connection = DriverManager.getConnection(url);

            connection.setAutoCommit(autoCommit);
            connection.setTransactionIsolation(Connection.TRANSACTION_READ_COMMITTED);
            return connection;
        } catch (Exception e) {
            log.error(e.getMessage(), e);

            throw new HermesException(e);
        }
    }

    protected Connection newProxyInstance(Connection connection) {
        return (Connection) Proxy.newProxyInstance(getClass().getClassLoader(), new Class[] { Connection.class },
                new ObjectPoolProxy<Connection>(connection, this, "close"));
    }

    @Override
    protected void closeObject(Connection connection) {
        DbUtils.closeQuietly(connection);
    }

    public boolean beforeCheckin(Connection connection) {
        try {
            if (connection.isClosed()) {
                return false;
            } else {
                if (!connection.getAutoCommit()) {
                    connection.rollback();
                }
            }
        } catch (SQLException ex) {
            log.warn("beforeCheckin failed:" + ex.getMessage(), ex);
            return false;
        }

        return true;
    }
}