(Java) Send Encrypted Email to Multiple Recipients

Demonstrates how to create and send an S/MIME encrypted email to multiple recipients. The digital certificate of each recipient is required. The encrypting/sending process uses each recipient's digital certificate (which internally contains the public key). Each recipient decrypts the received email using his/her private key.

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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.mymailserver.com");

    // Load each recipient's certificate into a Chilkat certificate object.
    // This example loads the certificates from files.  However, the Chilkat
    // certificate object provides other means for loading certificates,
    // such as from in-memory PEM strings, or in-memory binary DER encoded form, etc.
    CkCert cert1 = new CkCert();
    boolean success = cert1.LoadFromFile("recipient1.cer");
    if (success != true) {
        System.out.println(cert1.lastErrorText());
        return;
        }

    CkCert cert2 = new CkCert();
    success = cert2.LoadFromFile("recipient2.cer");
    if (success != true) {
        System.out.println(cert2.lastErrorText());
        return;
        }

    CkCert cert3 = new CkCert();
    success = cert3.LoadFromFile("recipient3.cer");
    if (success != true) {
        System.out.println(cert3.lastErrorText());
        return;
        }

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

    email.put_Subject("This email is encrypted and sent to 3 recipients");
    email.put_Body("This is an S/MIME encrypted mail sent to 3 recipients");
    email.put_From("Chilkat Support <support@chilkatsoft.com>");

    // Make each of the certificates available for encrypting the email
    // by calling AddEncryptCert for each.
    success = email.AddEncryptCert(cert1);
    if (success == true) {
        success = email.AddEncryptCert(cert2);
        }

    if (success == true) {
        success = email.AddEncryptCert(cert3);
        }

    if (success != true) {
        System.out.println(email.lastErrorText());
        return;
        }

    // Add 3 recipients to the email (2 TO addresses, and 1 CC address)
    success = email.AddTo("Recipient 1","admin@cknotes.com");
    success = email.AddTo("Recipient 2","somebody001122@yahoo.com");
    success = email.AddCC("Recipient 3","somebody123xyz@gmail.com");

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

    // Send the encrypted email...
    success = mailman.SendEmail(email);
    if (success != true) {
        System.out.println(mailman.lastErrorText());
        }
    else {
        System.out.println("Encrypted Email Sent!");
        }
  }
}