throw new IllegalArgumentException("value to key is not an arraylist, the value class is: " + get(key).getClass().getName());
throw new IllegalArgumentException( "value to key is not an arraylist: " + key.getClass().getName() + "(" + key.toString() + ") :" + get(key).getClass().getName() + "(" + get(key).toString() + ")");
    public ArrayList getArrayList(Object key) {        try {            return (ArrayList) get(key);        } catch (ClassCastException e) {            throw new IllegalArgumentException("value to key is not an arraylist, the value class is: " + get(key).getClass().getName());        }    }