public function addDomain($domain)
    {
        if (!isset($this->domains[$domain])) {
            $this->domains[$domain] = $domain;
        }

        return $this;
    }
public function addDomain($domain)
    {
        if (!isset($this->domains[$domain])) {
            $this->domains[$domain] = $domain;
        }

        return $this;
    }
public function addDomain ( $ domain ) { if ( ! isset ( $ this -> domains [ $ domain ] ) ) { $ this -> domains [ $ domain ] = $ domain ; } return $ this ; }
Adding a domain to the list.

@param string $domain fully qualified name of the domain object

@return self
Adding a domain to the list .