/*
 Simple Javascript Object Pool
 Copyright 2005 Joshua Eichorn

 This library is free software; you can redistribute it and/or
 modify it under the terms of the GNU Lesser General Public
 License as published by the Free Software Foundation; either
 version 2.1 of the License, or (at your option) any later version.
  
 This library is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 Lesser General Public License for more details.
  
 You should have received a copy of the GNU Lesser General Public
 License along with this library; if not, write to the Free Software
 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
*/

/**
 * A simple object pool written to be used with JPSpan
 * 
 * Automatically grows as needed
 * 
 * @author Joshua Eichorn <josh@bluga.net>
 * @copyright Joshua Eichorn 2005
 * @license lgpl http://www.gnu.org/copyleft/lesser.html
 */
function objectPool() {
	this.pool = new Array();

	this.avail = new Array();
}

/**
 * Should be overridden, creates a new object and returns it
 */
objectPool.prototype.createObject = function() {
	return new Object();
}

/**
 * Grabs a new object from the pool
 */
objectPool.prototype.getObject = function() {
	// see if we have any objects in the avail array
	if (this.avail.length == 0) {
		var o = this.createObject();
		o.poolId = this.pool.length;
		this.pool.push(o);
		this.avail.push(o.poolId);
	}

	var poolId = this.avail.pop();
	//alert('objectPool.getObject poolId: '+poolId);
	return this.pool[poolId];
}

/**
 * returns an object to the pool
 */
objectPool.prototype.returnObject = function(poolId) {
	this.avail.push(poolId);
}