(Java) Download IMAP Message Set using FetchBundle

Demonstrates how to read IMAP emails using the FetchBundle method.

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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.

    CkImap imap = new CkImap();

    // Connect using TLS.
    imap.put_Ssl(true);
    imap.put_Port(993);
    boolean success = imap.Connect("imap.example.com");
    if (success != true) {
        System.out.println(imap.lastErrorText());
        return;
        }

    // Authenticate
    success = imap.Login("email_account_login","email_account_password");
    if (success != true) {
        System.out.println(imap.lastErrorText());
        return;
        }

    // Select an IMAP mailbox
    success = imap.SelectMailbox("Inbox");
    if (success != true) {
        System.out.println(imap.lastErrorText());
        return;
        }

    // Search for messages with the word "test" in the subject.
    boolean fetchUids = true;
    CkMessageSet messageSet = imap.Search("Subject test",fetchUids);
    if (imap.get_LastMethodSuccess() != true) {
        System.out.println(imap.lastErrorText());
        return;
        }

    // Download the messages in a single call to FetchBundle.
    // 
    // This only makes sense if the number of emails to be downloaded is not too large.  
    // For example, you wouldn't want to download 10000 emails in a single call to FetchBundle.
    // Why? For two reasons:  (1) It could potentially cause an out-of-memory condition, and 
    // (2) it would take an extremely large amount of time.  The longer the amount of time,
    // the greater the likelihood of some kind of external networking or server problem occuring,
    // and if it happens, then you would need to re-download everything from the beginning again.
    // For large numbers of emails, it's better to loop over the emails in the message set
    // and download/process one at a time as shown here: Download IMAP Messages One at a Time
    // Downloading one message at a time makes it possible to resume the downloads rather than restart the entire operation all over again.

    // If the message set is reasonable in size, you can download all at once using FetchBundle:

    System.out.println("Number of messages = " + messageSet.get_Count());

    CkEmailBundle bundle = imap.FetchBundle(messageSet);
    if (imap.get_LastMethodSuccess() == false) {

        System.out.println(imap.lastErrorText());
        return;
        }

    // Display the Subject and From of each email.
    int i = 0;
    int numEmails = bundle.get_MessageCount();
    while (i < numEmails) {
        CkEmail email = bundle.GetEmail(i);

        System.out.println(email.getHeaderField("Date"));
        System.out.println(email.subject());
        System.out.println(email.ck_from());
        System.out.println("--");

        i = i+1;
        }
  }
}