private X509Certificate getCertificate(final String alias)
      throws NoSuchAlgorithmException, InvalidKeySpecException {
    if (aliasCertificateMap.containsKey(alias)) {
      return (X509Certificate) aliasCertificateMap.get(alias);
    }
    return null;
  }
An implementation of {@link Authenticator} that uses PKCS.
geode-dunit/src/main/java/org/apache/geode/security/templates/PKCSAuthenticator.java