Como cargar este POOL?

[SPAWN3000]

Encontré este código en Javahispano:

1. Link: http://www.javahispano.org/contenidos/es/pool_de_objetos_ii/
Y EN LOS COMENTARIOS jmarranz propuso algo que no me quedo muy claro...

2. Es necesario crear un servlet para poder darle uso correcto a esta clase?

3. Implemente el Main y la conexión, pero lo normal, o el paso siguiente, es que uno cree un Statement a partir del objeto que en este caso seria obj

Asi que deberia ser:
Statement obj = conexion.createStatement();
String UserQuery = "SELECT * FROM usuarios";
Pero la función es tipo object:
No se como finaliza para obtener el cursor final de conexión?

JDBCConnectionPool.java

Código:

import java.sql.DriverManager;
import java.sql.SQLException;
import java.sql.Connection;
import java.sql.*;

public class JDBCConnectionPool extends ObjectPool{
    
    private String dsn, usr, pwd;
    
    public static void main(String[] args){
    	String url = "jdbc:sybase:Tds:VISTAESCRITORIO:5000/Pruebas";
    	String Driver = "com.sybase.jdbc3.jdbc.SybDriver";
    	JDBCConnectionPool obj = new JDBCConnectionPool(Driver,url,"sa","1234567");
    }
    public JDBCConnectionPool( String driver, String dsn, String usr, String pwd )
    {
        try
        {
            Class.forName( driver ).newInstance();
        }
        catch( Exception e )
        {
            e.printStackTrace();
        }
        this.dsn = dsn;
        this.usr = usr;
        this.pwd = pwd;
    }
    
    Object create() throws SQLException
    {
        return( DriverManager.getConnection( dsn, usr, pwd ) );
    }
    
    boolean validate( Object o )
    {
        try
        {
            return( ! ( ( Connection ) o ).isClosed() );
        }
        catch( SQLException e )
        {
            e.printStackTrace();
            return false;
        }
    }
    
    void expire( Object o )
    {
        try
        {
            ( ( Connection ) o ).close();
        }
        catch( SQLException e )
        {
            e.printStackTrace();
        }
    }
    
    public Connection borrowConnection() throws SQLException
    {
        try
        {
            return( ( Connection ) super.checkOut() );
        }
        catch( Exception e )
        {
            throw( (SQLException) e );
        }
    }
    
    public void returnConnection( Connection c )
    {
        super.checkIn( c );
    }
}

ObjectPool.java

Código:

// Copyright (c) 1998 Thomas E. Davis

import java.util.Enumeration;
import java.util.Hashtable;

public abstract class ObjectPool 
{
    private long expirationTime;
    private long lastCheckOut;

    private Hashtable locked;
    private Hashtable unlocked;
    
    private CleanUpThread cleaner;
    
    ObjectPool()
    {
        expirationTime = ( 1000 * 60 ); // 60 seconds   

        locked = new Hashtable();         
        unlocked = new Hashtable();
        
        lastCheckOut = System.currentTimeMillis();

        cleaner = new CleanUpThread( this, expirationTime );
        cleaner.start();
    }
    
    abstract Object create() throws Exception;
    
    abstract boolean validate( Object o );
    
    abstract void expire( Object o );
    
    synchronized Object checkOut() throws Exception
    {
        long now = System.currentTimeMillis();      
        lastCheckOut = now;
        Object o;              
        
        if( unlocked.size() > 0 )
        {
            Enumeration e = unlocked.keys();  
            
            while( e.hasMoreElements() )
            {
                o = e.nextElement();        

                if( validate( o ) )
                {
                    unlocked.remove( o );
                    locked.put( o, new Long( now ) );                
                    return( o );
                }
                else
                {
                    unlocked.remove( o );
                    expire( o );
                    o = null;
                }
            }
        }        
        
        o = create();        
        
        locked.put( o, new Long( now ) ); 
        return( o );
    }
    
    synchronized void checkIn( Object o )
    {
        if( o != null )
        {
            locked.remove( o );
            unlocked.put( o, new Long( System.currentTimeMillis() ) );
        }
    }
    
    synchronized void cleanUp()
    {
        Object o;

        long now = System.currentTimeMillis();
        
        Enumeration e = unlocked.keys();  
        
        while( e.hasMoreElements() )
        {
            o = e.nextElement();        

            if( ( now - ( ( Long ) unlocked.get( o ) ).longValue() ) > expirationTime )
            {
                unlocked.remove( o );
                expire( o );
                o = null;
            }
        }

        System.gc();
    }
}

class CleanUpThread extends Thread
{
    private ObjectPool pool;
    private long sleepTime;
    
    CleanUpThread( ObjectPool pool, long sleepTime )
    {
        this.pool = pool;
        this.sleepTime = sleepTime;
    }
    
    public void run()
    {
        while( true )
        {
            try
            {
                sleep( sleepTime );
            }
            catch( InterruptedException e )
            {
                // ignore it
            }         
            pool.cleanUp();
        }
    }
}