certGen.setSerialNumber(BigInteger.valueOf(1));
certGen.setIssuerDN(PrincipalUtil.getSubjectX509Principal(caCert));
certGen.setNotBefore(new Date(System.currentTimeMillis() - 50000));
certGen.setNotAfter(new Date(System.currentTimeMillis() + 50000));
certGen.setSubjectDN(new X509Principal("CN=Test Intermediate Certificate"));
certGen.setPublicKey(intKey);
certGen.setSignatureAlgorithm("SHA256WithRSAEncryption");
certGen.addExtension(X509Extensions.AuthorityKeyIdentifier, false, new AuthorityKeyIdentifierStructure(caCert));
certGen.addExtension(X509Extensions.SubjectKeyIdentifier, false, new SubjectKeyIdentifierStructure(intKey));