certificateGenerator.addExtension(Extension.authorityInfoAccess, false, authorityInformationAccess);
}
if (null != keyUsage) {
certificateGenerator.addExtension(Extension.keyUsage, true, keyUsage);
}
JcaContentSignerBuilder signerBuilder = new JcaContentSignerBuilder(signatureAlgorithm);
signerBuilder.setProvider("BC");