jQuery.Hashtable  = function()
{ 
	this.items=new Array();
	this.itemsCount=0;
	this.add = function(key,value)
	{
		if(!this.containsKey(key))
		{
			this.items[key]=value;
			this.itemsCount++;
		}
		else
			throw "key '"+key+"' allready exists."
	}
	this.get=function(key)
	{
		if(this.containsKey(key))
			return this.items[key];
		else
			return null;
	}

	this.remove = function(key)
	{
		if(this.containsKey(key))
		{
			delete this.items[key];
			this.itemsCount--;
		}
		else
			throw "key '"+key+"' does not exists."
	}
	this.containsKey= function(key)
	{
		return typeof(this.items[key])!="undefined";
	}
	this.clear = function()
	{
		this.items=new Array();
		itemsCount=0;
	}
	this.size = function()
	{
		return this.itemsCount;
	}
	this.isEmpty = function()
	{
		return this.size()==0;
	}
};