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Java

Send Signed Email using PFX File

Demonstrates how to send a signed email using a digital certificate w/ private key stored in a PFX file.

Chilkat Java Downloads

Java
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[])
  {
    boolean success = false;

    //  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");

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

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

    //  Indicate that the email should be sent signed.
    email.put_SendSigned(true);

    //  Tell the mailman to use a PFX file as a source for locating
    //  the certificate and private key required for signing.
    //  The certificate chosen for signing will be the one that
    //  matches the sender's email address, which also has
    //  a private key.  All intermediate certs in the chain of 
    //  authentication, up to and including the root, will
    //  be included in the signature.
    success = mailman.AddPfxSourceFile("/pfx_files/chilkatsoft_secret.pfx","secret");
    if (success != true) {
        System.out.println(mailman.lastErrorText());
        return;
        }

    //  Signed email can be sent in two different ways.  
    //  In a multipart/signed email, the signature is attached as a separate MIME part.
    //  In an opaque email (signedData) the content of the email is encapsulated within the signature
    //  and the email is sent as "application/pkcs7-mime". 
    //  Either should be fine, but some receiving systems might require one or the other..
    mailman.put_OpaqueSigning(false);

    //  Send a signed email.
    success = mailman.SendEmail(email);
    if (success != true) {
        System.out.println(mailman.lastErrorText());
        }
    else {
        //  The LastErrorText property provides information
        //  even when successful.
        System.out.println(mailman.lastErrorText());
        System.out.println("Mail Sent!");
        }
  }
}