public function createFromComposerJson($composer)
    {
        $sections = $this->getAutoloadSectionNames($composer);

        if (empty($sections)) {
            return array();
        }

        $validators = array();
        foreach ($sections as $section) {
            $validators[] = $this->createValidatorsFromSection($section, $composer[$section]);
        }

        return call_user_func_array('array_merge', $validators);
    }