import org.spongycastle.asn1.x509.GeneralName; //导入依赖的package包/类
private Certificate generateSelfSignedCertChain(KeyPair kp, X500Name subject, String hostname)
        throws CertificateException, OperatorCreationException, IOException {
    SecureRandom rand = new SecureRandom();
    PrivateKey privKey = kp.getPrivate();
    PublicKey pubKey = kp.getPublic();
    ContentSigner sigGen = new JcaContentSignerBuilder(DEFAULT_SIG_ALG).build(privKey);

    SubjectPublicKeyInfo subPubKeyInfo = new SubjectPublicKeyInfo(
            ASN1Sequence.getInstance(pubKey.getEncoded()));

    Date now = new Date(); // now

    /* force it to use a English/Gregorian dates for the cert, hardly anyone
       ever looks at the cert metadata anyway, and its very likely that they
       understand English/Gregorian dates */
    Calendar c = new GregorianCalendar(Locale.ENGLISH);
    c.setTime(now);
    c.add(Calendar.YEAR, 1);
    Time startTime = new Time(now, Locale.ENGLISH);
    Time endTime = new Time(c.getTime(), Locale.ENGLISH);

    X509v3CertificateBuilder v3CertGen = new X509v3CertificateBuilder(
            subject,
            BigInteger.valueOf(rand.nextLong()),
            startTime,
            endTime,
            subject,
            subPubKeyInfo);

    if (hostname != null) {
        GeneralNames subjectAltName = new GeneralNames(
                new GeneralName(GeneralName.iPAddress, hostname));
        v3CertGen.addExtension(X509Extension.subjectAlternativeName, false, subjectAltName);
    }

    X509CertificateHolder certHolder = v3CertGen.build(sigGen);
    return new JcaX509CertificateConverter().getCertificate(certHolder);
}
 

import org.spongycastle.asn1.x509.GeneralName; //导入依赖的package包/类
public static X509Certificate generateCertificate(KeyPair pair)
        throws InvalidKeyException, NoSuchProviderException, SignatureException
{
    // generate the certificate
    X509V3CertificateGenerator certGen = new X509V3CertificateGenerator();

    certGen.setSerialNumber(BigInteger.valueOf(System.currentTimeMillis()));
    certGen.setIssuerDN(new X500Principal("CN=Restcomm Android SDK"));
    certGen.setNotBefore(new Date(System.currentTimeMillis() - 50000));
    // TODO: using 1 day for now, need to increase that
    certGen.setNotAfter(new Date(System.currentTimeMillis() + 86400000));
    certGen.setSubjectDN(new X500Principal("CN=Restcomm Android SDK"));
    certGen.setPublicKey(pair.getPublic());
    certGen.setSignatureAlgorithm("SHA1withECDSA");

    certGen.addExtension(X509Extensions.BasicConstraints, true, new BasicConstraints(false));
    certGen.addExtension(X509Extensions.KeyUsage, true, new KeyUsage(KeyUsage.digitalSignature | KeyUsage.keyEncipherment));
    certGen.addExtension(X509Extensions.ExtendedKeyUsage, true, new ExtendedKeyUsage(KeyPurposeId.id_kp_serverAuth));
    certGen.addExtension(X509Extensions.SubjectAlternativeName, false, new GeneralNames(new GeneralName(GeneralName.rfc822Name, "[email protected]")));

    // provider is Bouncy Castle
    return certGen.generateX509Certificate(pair.getPrivate(), "BC");
}