(Java) Send Email to Distribution List

Sends the same email to a list of 1000 email addresses in 50 sends where each email has 20 recipients.

Note: Chilkat is not intended nor designed for mass emailing. A solution such as this might be used for a corporate emailing to employees, or an emailing to newsletter subscribers.

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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.

    CkMailMan mailman = new CkMailMan();
    boolean success;

    mailman.put_SmtpHost("smtp.mymailserver.com");
    mailman.put_SmtpPort(465);
    mailman.put_SmtpSsl(true);
    mailman.put_SmtpUsername("myUsername");
    mailman.put_SmtpPassword("myPassword");

    // Create a new email object
    CkEmail email = new CkEmail();
    email.put_Subject("This is a test");
    email.put_Body("This is a test");
    email.put_From("Senders Name <sender@example.com>");
    email.AddTo("Subscribers","subscribers@example.com");

    CkBinData bdMime = new CkBinData();
    mailman.RenderToMimeBd(email,bdMime);

    // Load a file containing one email address per line.
    CkStringTable distList = new CkStringTable();
    success = distList.AppendFromFile(1000,"utf-8","qa_data/distList.txt");
    if (success == false) {
        System.out.println(distList.lastErrorText());
        return;
        }

    CkStringBuilder sbRecipients = new CkStringBuilder();

    int i = 0;
    int szDistList = distList.get_Count();
    int j = 0;
    while (i < szDistList) {

        // Build a list of comma-separated recipients.
        if (j > 0) {
            sbRecipients.Append(",");
            }

        sbRecipients.Append(distList.stringAt(i));

        i = i+1;
        j = j+1;

        // If we have 20 recipients, or we have the final recipient in the final chunk, then send.
        if ((j == 20) || (i == szDistList)) {
            success = mailman.SendMimeBd("sender@example.com",sbRecipients.getAsString(),bdMime);
            if (success != true) {
                System.out.println(mailman.lastErrorText());
                return;
                }

            j = 0;
            sbRecipients.Clear();
            }

        }

    success = mailman.CloseSmtpConnection();
    if (success != true) {
        System.out.println("Connection to SMTP server not closed cleanly.");
        }

    System.out.println("Email sent to distirbution list.");
  }
}