/* ======================================================================
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.util.logging.*;



import org.bodington.server.BuildingServer;
import org.bodington.pool.*;

import java.sql.*;
import java.util.Hashtable;

public class ConnectionPool extends ObjectPool
	{
	private String url;
	private String user_name;
	private String password;
	

	public ConnectionPool( int size, int user_max, String url, String user_name, String password )
		throws ObjectPoolException
		{
		this.url = url;
		this.user_name = user_name;
		this.password = password;

		init( size, user_max, 30000, 30000 );
		}

	public ConnectionPool( int size, int user_max, int greedy_max, String url, String user_name, String password )
		throws ObjectPoolException
		{
		this.url = url;
		this.user_name = user_name;
		this.password = password;

		init( size, user_max, 30000, greedy_max, 30000 );
		}
        
	protected Object createObject()
		throws Exception
		{
		return DriverManager.getConnection( url, user_name, password );
		}

		
	protected Object initialiseObject( Object o )
		throws Exception
		{
		Connection connection = (Connection)o;
		Statement statement = null;
		ResultSet results = null;
		
		try
			{
			connection.setAutoCommit( true );
			// force exception on connections that are dead
			statement = connection.createStatement();
			results = statement.executeQuery( "SELECT * FROM objects WHERE id IS NULL" );
			results.close();
			
			//didn't throw exception so it's OK to use this connection.
			return connection;
			}
		catch ( SQLException ex )
			{
			Logger.getLogger( "org.bodington" ).logp( 
			    Level.SEVERE, 
			    "ConnectionPool", 
			    "initialiseObject", 
			    "ConnectionPool.initialiseObject() SQLException trying to init connection - got rid of it.", 
			    ex );
			}
		finally
			{
			try
				{
				if ( results != null )
					results.close();
				if ( statement != null )
					statement.close();
				}
			catch ( SQLException sqlex )
				{
				}
			}
						
		// erase this dead connection
		try
			{
			if ( !connection.isClosed() )
				connection.close();
			}
		catch ( SQLException sqlex )
			{
			}
						
		// and make a fresh one
		connection = DriverManager.getConnection( url, user_name, password );
		connection.setAutoCommit( true );
		return connection;
		}
		
	protected void poolObject( Object o )
		throws Exception
		{
		}
		
		
	public Connection getConnection( Object user )
		throws ObjectPoolException
		{
		Logger.getLogger( "org.bodington" ).fine( "ConnectionPool.getConnection( \"" + user + "\" );" );
		return (Connection)getObject( user );
		}

		
	public void freeConnection( Connection free_con )
		throws ObjectPoolException
		{
		freeObject( free_con );
		}
	}