values.add(0, new ScopeState());
    }

    protected ScopeState getScopeState() {
        if (values.isEmpty()) {
            throw new OutOfScopeException("Cannot access session scope outside of a scoping block");
        }
        return values.get(0);
    }

    public void exit() {
        if (values.isEmpty()) {
            throw new IllegalStateException();
        }
        values.remove(0);
    }