(Java) Sending S/MIME Encrypted Email

Sends an encrypted email using the recipient's digital certificate from a .cer file.

Chilkat Java Downloads Java Libs for Windows, MacOS, Linux, Alpine Linux, Solaris Java Libs for Android

import com.chilkatsoft.*;

public class ChilkatExample {

  static {
    try {
        System.loadLibrary("chilkat");
    } catch (UnsatisfiedLinkError e) {
      System.err.println("Native code library failed to load.\n" + e);
      System.exit(1);
    }
  }

  public static void main(String argv[])
  {
    // This example requires the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    // The mailman object is used for sending and receiving email.
    CkMailMan mailman = new CkMailMan();

    // Set the SMTP server.
    mailman.put_SmtpHost("smtp.comcast.net");

    // Load the .cer file into a certificate object.
    // When sending S/MIME encrypted email, it is the recipient's
    // certificate that is used for encryption.  Only the public key
    // is needed to encrypt.  The recipient is the only
    // one possessing the private key, and therefore is the only
    // one able to decrypt.
    CkCert cert = new CkCert();
    boolean success = cert.LoadFromFile("cknotes.cer");
    if (success != true) {
        System.out.println(cert.lastErrorText());
        return;
        }

    // Create a new email object
    CkEmail email = new CkEmail();

    email.put_Subject("This email is encrypted");
    email.put_Body("This is a digitally encrypted mail");
    email.put_From("Chilkat Support <support@chilkatsoft.com>");
    success = email.AddTo("Chilkat Blog","admin@cknotes.com");

    // Indicate that the email is to be sent encrypted.
    email.put_SendEncrypted(true);

    // Specify the certificate to be used for encryption.
    success = email.SetEncryptCert(cert);

    success = mailman.SendEmail(email);
    if (success != true) {
        System.out.println(mailman.lastErrorText());
        }
    else {
        System.out.println("Mail Sent!");
        }
  }
}