public void addRestriction(Restriction newRestriction)
        {
        	//Check that it hasn't been added yet
        	for(Restriction r: restrictions){
        		if(r.getIdentifier().equals(newRestriction.getIdentifier()))
        			throw new IllegalArgumentException("There's already a restriction with that identifier. Identifiers need to be unique.");
        		}
        	//We add it normally
        	restrictions.add(newRestriction);
        }