protected function init() {
    if ($this->getConfig()->get('drush.bin')) {
      $this->executable = str_replace(' ', '\\ ', $this->getConfig()->get('drush.bin'));
    }
    else {
      $this->executable = 'drush';
    }

    if (!isset($this->dir)) {
      $this->dir($this->getConfig()->get('drush.dir'));
    }
    if (!isset($this->uri)) {
      $this->uri = $this->getConfig()->get('drush.uri');
    }
    if (!isset($this->alias)) {
      $this->alias($this->getConfig()->get('drush.alias'));
    }
    if (!isset($this->interactive)) {
      $this->interactive(FALSE);
    }
    if (!isset($this->ansi)) {
      $this->ansi($this->getConfig()->get('drush.ansi'));
    }

    $this->defaultsInitialized = TRUE;
  }