public int getTotalWeight()
	{
		if (!items.isEmpty())
		{
	    	int total = 0;
	        Set<String> keys = items.keySet();
	        
	        for (String key : keys)
	        {
	        	total += this.items.get(key).getWeight();
	        }
	        
	        return total;
		}
		else
		{
			return 0;
		}
	}