Before declining to grant a license or conditioning or limiting a license, or suspending or revoking a license previously granted, the director shall give notice to the applicant or licensee personally, or by mail addressed to his last known address, and afford him an opportunity to appear and be heard with respect thereto at a time and place specified in such notice. Such applicant or licensee shall have the right to be heard in person or by attorney, and to offer evidence pertinent to the subject of the hearing, and to that end to invoke the powers of the director with respect to the compulsory attendance of witnesses and the production of books, accounts, papers, records and documents by subpoena. A duly certified copy of the order of the director of such hearing shall be served upon the applicant or the licensee in the manner provided by section twenty of this act.
N.J.S. § 4:12A-34