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Java Requires Chilkat v11.0.0+

Mark IMAP Email as Read/Unread (Seen/Unseen)

Demonstrates how to mark emails as read or unread.

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Chilkat2 Java
import com.chilkatsoft.chilkat2.ChilkatException;
import com.chilkatsoft.chilkat2.Email;
import com.chilkatsoft.chilkat2.Imap;

public class ChilkatExample {

    public static void main(String[] args) {
        // This example assumes the Chilkat API to have been previously unlocked.
        // See Global Unlock Sample for sample code.

        Imap imap = new Imap();

        // Connect to an IMAP server.
        // Use TLS
        imap.setSsl(true);
        imap.setPort(993);
        try {
            imap.connect("imap.example.com");

            // Login
            imap.login("myLogin", "myPassword");

            // Select an IMAP mailbox
            imap.selectMailbox("Inbox");
        } catch (ChilkatException e) {
            System.out.println(e.getLastErrorText());
            return;
        }

        // Set PeekMode so that downloaded messages are not
        // automatically marked as seen.
        imap.setPeekMode(true);

        // The NumMessages property contains the number of messages
        // in the currently selected mailbox.
        int numMsgs = imap.getNumMessages();
        if (numMsgs == 0) {
            return;
        }

        Email email = new Email();
        for (int i = 1; i <= numMsgs; i++) {
            // Download each email by sequence number (not UID)
            try {
                imap.fetchEmail(false, i, false, email);
            } catch (ChilkatException e) {
                System.out.println(e.getLastErrorText());
                return;
            }

            // If desired, mark the email as SEEN.  There are two
            // ways to do it:

            // 1) Set the flag directly by using the sequence number
            // Indicate that we are passing a sequence number and
            // not a UID:
            boolean bIsUid = false;
            // Set the SEEN flag = 1 to mark the email as SEEN,
            // or set it to 0 to mark it as not-seen.
            try {
                imap.setFlag(i, bIsUid, "SEEN", 1);

                // 2) Alternatively, we can use the email object.
                // When an email is downloaded from the IMAP server
                // Chilkat will add a "ckx-imap-uid" header to the email.
                // This makes it possible to know the UID associated with
                // the email.  (This is not the sequence number, which may change
                // from session to session, but the UID which does not change.
                // The SetMailFlag method is identical to SetFlag, except
                // it gets the UID from the ckx-imap-uid header.
                // For example:
                imap.setMailFlag(email, "SEEN", 1);
            } catch (ChilkatException e) {
                System.out.println(e.getLastErrorText());
                return;
            }
        }

        // Disconnect from the IMAP server.
        imap.disconnect();
    }
}