}

    public void mutate(String method, Runnable action) {
        if (!task.getState().isConfigurable()) {
            throw new IllegalStateException(format(method));
        }
        action.run();
    }

    public <T> T mutate(String method, Callable<T> action) {
        if (!task.getState().isConfigurable()) {
            throw new IllegalStateException(format(method));
        }