/* ======================================================================
 The Bodington System Software License, Version 1.0
 
 Copyright (c) 2001 The University of Leeds.  All rights reserved.
 
 Redistribution and use in source and binary forms, with or without
 modification, are permitted provided that the following conditions are
 met:
 
 1.  Redistributions of source code must retain the above copyright notice,
 this list of conditions and the following disclaimer.
 
 2.  Redistributions in binary form must reproduce the above copyright
 notice, this list of conditions and the following disclaimer in the
 documentation and/or other materials provided with the distribution.
 
 3.  The end-user documentation included with the redistribution, if any,
 must include the following acknowledgement:  "This product includes
 software developed by the University of Leeds
 (http://www.bodington.org/)."  Alternately, this acknowledgement may
 appear in the software itself, if and wherever such third-party
 acknowledgements normally appear.
 
 4.  The names "Bodington", "Nathan Bodington", "Bodington System",
 "Bodington Open Source Project", and "The University of Leeds" must not be
 used to endorse or promote products derived from this software without
 prior written permission. For written permission, please contact
 d.gardner@leeds.ac.uk.
 
 5.  The name "Bodington" may not appear in the name of products derived
 from this software without prior written permission of the University of
 Leeds.
 
 THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 WARRANTIES, INCLUDING, BUT NOT LIMITED TO,  TITLE,  THE IMPLIED WARRANTIES
 OF QUALITY  AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO
 EVENT SHALL THE UNIVERSITY OF LEEDS OR ITS CONTRIBUTORS BE LIABLE FOR
 ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
 GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
 ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 POSSIBILITY OF SUCH DAMAGE.
 =========================================================
 
 This software was originally created by the University of Leeds and may contain voluntary
 contributions from others.  For more information on the Bodington Open Source Project, please
 see http://bodington.org/
 
 ====================================================================== */

package org.bodington.database;

import java.sql.Connection;

/**
 * Any class that to manage database connection pooling for Bodington 
 * should implement this interface.
 * @author buckett
 */
public interface ConnectionPool
{
    /**
     * Get a connection.
     * @param user An object to associate this connection with. This can be used
     * to enforce per user limits. It can be null, in which case no limits should be
     * enforced.
     * @return A database connection. Not null.
     * @throws ConnectionPoolException If a connection could not be returned or the
     * connection limit has been hit.
     */
    public Connection getConnection(Object user) throws ConnectionPoolException;

    /**
     * Put a database connection back in the pool.
     * @param free_con The database connection to return to the pool.
     * @throws ConnectionPoolException If something we wrong return the item to
     * the pool. Most of the time this can be ignored.
     */
    public void freeConnection(Connection free_con) throws ConnectionPoolException;
}