if (args.length != 3)
{
System.err.println("usage: ReadLargeEncryptedMail pkcs12Keystore password outputFile");
System.exit(0);
}
//
// Open the key store
//
KeyStore ks = KeyStore.getInstance("PKCS12", "BC");
String keyAlias = ExampleUtils.findKeyAlias(ks, args[0], args[1].toCharArray());
//
// find the certificate for the private key and generate a
// suitable recipient identifier.
//
X509Certificate cert = (X509Certificate)ks.getCertificate(keyAlias);
RecipientId recId = new RecipientId();
recId.setSerialNumber(cert.getSerialNumber());
recId.setIssuer(cert.getIssuerX500Principal().getEncoded());
//
// Get a Session object with the default properties.
//
Properties props = System.getProperties();
Session session = Session.getDefaultInstance(props, null);
MimeMessage msg = new MimeMessage(session, new SharedFileInputStream("encrypted.message"));
SMIMEEnvelopedParser m = new SMIMEEnvelopedParser(msg);
RecipientInformationStore recipients = m.getRecipientInfos();
RecipientInformation recipient = recipients.get(recId);
MimeBodyPart res = SMIMEUtil.toMimeBodyPart(recipient.getContentStream(ks.getKey(keyAlias, null), "BC"));
ExampleUtils.dumpContent(res, args[2]);