code: @Override
      public void handle(final Callback[] callbacks) throws IOException,
              UnsupportedCallbackException {
          for (Callback callback : callbacks) {
              if (callback instanceof CertificateVerificationCallback) {
                  verify(CertificateVerificationCallback.class.cast(callback));
              } else {
                  throw new UnsupportedCallbackException(callback);
              }
          }
      }
docs: {@inheritDoc}