Method importPlugin

/**
 * Loads all the plugin files for a particular type if no specific plugin is specified
 * otherwise only the specific plugin is loaded.
 *
 * @param   string               $type        The plugin type, relates to the subdirectory in the plugins directory.
 * @param   string               $plugin      The plugin name.
 * @param   boolean              $autocreate  Autocreate the plugin.
 * @param   DispatcherInterface  $dispatcher  Optionally allows the plugin to use a different dispatcher.
 *
 * @return  boolean  True on success.
 *
 * @since   1.5
 */
public static function importPlugin($type, $plugin = null, $autocreate = true, DispatcherInterface $dispatcher = null)
{
    static $loaded = [];
    // Check for the default args, if so we can optimise cheaply
    $defaults = false;
    if ($plugin === null && $autocreate === true && $dispatcher === null) {
        $defaults = true;
    }
    // Ensure we have a dispatcher now so we can correctly track the loaded plugins
    $dispatcher = $dispatcher ?: Factory::getApplication()->getDispatcher();
    // Get the dispatcher's hash to allow plugins to be registered to unique dispatchers
    $dispatcherHash = spl_object_hash($dispatcher);
    if (!isset($loaded[$dispatcherHash])) {
        $loaded[$dispatcherHash] = [];
    }
    if (!$defaults || !isset($loaded[$dispatcherHash][$type])) {
        $results = null;
        // Load the plugins from the database.
        $plugins = static::load();
        // Get the specified plugin(s).
        for ($i = 0, $t = \count($plugins); $i < $t; $i++) {
            if ($plugins[$i]->type === $type && ($plugin === null || $plugins[$i]->name === $plugin)) {
                static::import($plugins[$i], $autocreate, $dispatcher);
                $results = true;
            }
        }
        // Bail out early if we're not using default args
        if (!$defaults) {
            return $results;
        }
        $loaded[$dispatcherHash][$type] = $results;
    }
    return $loaded[$dispatcherHash][$type];
}