code: public void setClientCertificate(String clientCertificate, String keyPassword) {
          LOG.debug("use client certificate/password {}/********", clientCertificate);
          this.clientCertificate = clientCertificate;
          this.keyPassword = keyPassword;
      }
docs: Calls this to provide client certificate.
  
  @param clientCertificate client certificate file
  @param keyPassword       client certificate password