/**
     * Finds the plugin id which corresponds to the supplied class name.
     * @param clazz the class to look for
     * @return the plugin id for this class.
     */
    Optional<PluginId> findPluginForClass(Class<?> clazz);

        }

        return null;
    }

    @Override
    public Optional<PluginId> findPluginForClass(Class<?> clazz) {
        if (parent != null) {
            Optional<PluginId> result = parent.findPluginForClass(clazz);
            if (result.isPresent()) {
                return result;
            }
        }

    pluginClass: Class<*>
) {
    val jarsByPlugin = mutableMapOf<String, MutableList<File>>()
    if (isExternal(pluginClass)) {
        val registry = findPluginRegistry(project)
        val pluginId: String = registry.findPluginForClass(pluginClass)
            .map(PluginId::getId)
            .orElseGet { pluginClass.name }
        val pluginJar = findPluginJar(pluginClass)
        if (pluginJar != null) {