(Java) POP3 to SMTP Forwarder

Read a POP3 mailbox and forwards the email to another email address, keeping the recipients in the original email the same.

Note: This example requires Chilkat v11.0.0 or greater.

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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[])
  {
    boolean success = false;

    // This example requires the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    CkMailMan mailman = new CkMailMan();

    // Set the POP3 server's hostname
    mailman.put_MailHost("pop.example.com");

    // Set the POP3 login/password.
    mailman.put_PopUsername("MY_POP3_LOGIN");
    mailman.put_PopPassword("MY_POP3_PASSWORD");

    // Set the SMTP hostname for sending.
    mailman.put_SmtpHost("smtp.example.com");
    mailman.put_SmtpUsername("MY_SMTP_LOGIN");
    mailman.put_SmtpPassword("MY_SMTP_PASSWORD");

    String fromAddr = "me@example.com";
    String toAddr = "recipient@somewhere.com";

    // The the UIDLs for all email in the POP3 mailbox.
    CkStringTable stUidls = new CkStringTable();
    success = mailman.FetchUidls(stUidls);
    if (success == false) {
        System.out.println(mailman.lastErrorText());
        return;
        }

    // Just mark messages for delete, then delete at the end.
    mailman.put_ImmediateDelete(false);

    // Download the email from the server.  Call FetchMimeBd
    // because we don't want to load the emails into email objects.
    // (We'll delete the emails that are forwarded without error.)
    CkBinData bdMime = new CkBinData();

    int count = stUidls.get_Count();
    int i = 0;
    while (i < count) {
        String uidl = stUidls.stringAt(i);
        System.out.println("UIDL: " + uidl);

        success = mailman.FetchMimeBd(uidl,bdMime);
        if (success == false) {
            System.out.println(mailman.lastErrorText());
            return;
            }

        success = mailman.SendMimeBd(fromAddr,toAddr,bdMime);
        if (success == false) {
            System.out.println(mailman.lastErrorText());
            return;
            }

        success = mailman.DeleteByUidl(uidl);
        if (success == false) {
            System.out.println(mailman.lastErrorText());
            return;
            }

        i = i+1;
        }

    // Delete messages marked for delete.
    mailman.put_ImmediateDelete(true);
    success = mailman.Pop3EndSession();
    if (success == false) {
        System.out.println(mailman.lastErrorText());
        return;
        }

    System.out.println("Success.");
  }
}