class InstanceCertManager {

    public String getX509CertificateSigner() {

        // if configured not to send x.509 signer certs
        // then we'll return right away as null

        if (!responseSendX509SignerCerts) {
            return null;
        }

        if (caX509CertificateSigner == null) {
            synchronized (InstanceCertManager.class) {
                updateX509CertificateSigner();
            }
        }
        return caX509CertificateSigner;
    }

    public  InstanceCertManager(final PrivateKeyStore keyStore, Authorizer authorizer, HostnameResolver hostnameResolver,
            boolean readOnlyMode);

}