gistfile1.java

    private static void genCert
        (String id, String pass, File pubfile, File secfile)
        throws Exception
    {
        KeyPairGenerator  kpg = KeyPairGenerator.getInstance("RSA", "BC");
        kpg.initialize(2048);

        KeyPair sign_pair = kpg.generateKeyPair();
        KeyPair enc_pair = kpg.generateKeyPair();

        FileOutputStream    pubout = new FileOutputStream(pubfile);
        FileOutputStream    secout = new FileOutputStream(secfile);

        exportKP(secout, pubout, sign_pair,
                 enc_pair, id, pass.toCharArray());
    }


    private static void exportKP
        (OutputStream secout, OutputStream pubout, KeyPair sign_kp,
         KeyPair enc_kp, String id, char[] pass)
        throws Exception
    {
        secout = new ArmoredOutputStream(secout);
        pubout = new ArmoredOutputStream(pubout);

        PGPKeyPair rsakp_sign =
            new PGPKeyPair(PGPPublicKey.RSA_SIGN, sign_kp, new Date());
        PGPKeyPair rsakp_enc =
            new PGPKeyPair(PGPPublicKey.RSA_ENCRYPT, enc_kp, new Date());
        PGPDigestCalculator sha1Calc =
            new BcPGPDigestCalculatorProvider()
            .get(HashAlgorithmTags.SHA1);

        // Set up some defaults.
        PGPSignatureSubpacketGenerator hashgen =
            new PGPSignatureSubpacketGenerator();
        hashgen.setPreferredSymmetricAlgorithms
            (false, new int[] { SymmetricKeyAlgorithmTags.AES_256 });
        hashgen.setFeature(false, Features.FEATURE_MODIFICATION_DETECTION);

        PGPKeyRingGenerator keyRingGen =
            new PGPKeyRingGenerator
            (PGPSignature.POSITIVE_CERTIFICATION, rsakp_sign,
             id, sha1Calc, hashgen.generate(), null,
             new BcPGPContentSignerBuilder
             (rsakp_sign.getPublicKey().getAlgorithm(), HashAlgorithmTags.SHA1),
             new BcPBESecretKeyEncryptorBuilder
             (PGPEncryptedData.AES_256, sha1Calc).build(pass));

        keyRingGen.addSubKey(rsakp_enc);
        PGPSecretKeyRing secretkr = keyRingGen.generateSecretKeyRing();
        secretkr.encode(secout);
        secout.close();

        keyRingGen.generatePublicKeyRing().encode(pubout);
        pubout.close();
    }