code: @Override
      public boolean verify(final X509Certificate cert) {
          final List<String> algs = new ArrayList<String>(
                  getAlgorithms(MessageDigest.class.getSimpleName()));
          Collections.sort(algs);
          int max = 0;
          for (final String alg : algs) {
              if (alg.length() > max) {
                  max = alg.length();
              }
          }
          for (final String alg : algs) {
              MessageDigest digest;
              try {
                  digest = MessageDigest.getInstance(alg);
              } catch (NoSuchAlgorithmException e) {
                  return false;
              }
              byte[] hash;
              try {
                  hash = digest.digest(cert.getEncoded());
              } catch (CertificateEncodingException e) {
                  return false;
              }
              System.out.format("%" + max + "s: %s%n", alg,
                      Hex.encodeHexString(hash));
          }
          final Scanner scanner = new Scanner(System.in, Charset.defaultCharset()
                  .name()).useDelimiter(String.format("%n"));
          while (true) {
              System.out.format("%nAccept? (Y/N): [N]%n");
              try {
                  final String answer = scanner.next();
                  System.out.println(answer);
                  if (answer.equals("Y")) {
                      return true;
                  } else if (answer.equals("N")) {
                      return false;
                  }
              } catch (final NoSuchElementException e) {
                  return false;
              }
          }
      }
docs: Use the system console to prompt the user with each available hash.
  
  @param cert
  the certificate to verify
  @return <tt>true</tt> if the certificate is verified, <tt>false</tt>
  otherwise.