code: public Constraint createModel(final MathRandom random, final Element element) {
  		if (element == null) {
  			return null;
  		}
  		Class<? extends Constraint> classObject = null;
  		Constraint object = null;
  		try {
  			classObject = getClassObject(element);
  			Constructor<? extends Constraint> constructor = getConstructor(classObject);
  			object = getObject(random, element, constructor);
  		} catch (InvocationTargetException ex) {
  			throw new JFunkException("Could not initialise object of class " + classObject, ex.getCause());
  		} catch (Exception ex) {
  			throw new JFunkException("Could not initialise object of class " + classObject, ex);
  		}
  		putToCache(element, object);
  		return object;
  	}
docs: Generates an instance based on the data in the given object. The object's class will be
  determined by the class attribute of the element. IF the element contains an id attribute the
  generated instance is stored in a map using this id as key.