Java

Send a POP3 NOOP Command

Demonstrates the Chilkat MailMan.Pop3Noop method, which sends a POP3 NOOP command to the server. NOOP does nothing except elicit a positive response, which is useful for keeping a session alive or verifying the connection is still responsive. This example begins a POP3 session and sends a NOOP.

Background: NOOP ("no operation") is a standard keep-alive across many internet protocols. Servers often drop idle connections after a timeout; sending a periodic NOOP resets that timer so a long-running session stays open. It also serves as a cheap "are you still there?" probe — a successful reply confirms the socket and the authenticated session are still healthy.

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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;

    //  Demonstrates the MailMan.Pop3Noop method, which sends a POP3 NOOP command to the server.
    //  NOOP does nothing except elicit a positive response, which is useful for keeping a
    //  session alive or verifying the connection is still responsive.

    CkMailMan mailman = new CkMailMan();

    //  Configure the POP3 server connection.
    mailman.put_MailHost("pop.example.com");
    mailman.put_MailPort(995);
    mailman.put_PopSsl(true);
    mailman.put_PopUsername("user@example.com");
    mailman.put_PopPassword("myPassword");

    //  Begin a POP3 session.

    success = mailman.Pop3BeginSession();
    if (success == false) {
        System.out.println(mailman.lastErrorText());
        return;
        }

    //  Send a NOOP to keep the session alive.
    success = mailman.Pop3Noop();
    if (success == false) {
        System.out.println(mailman.lastErrorText());
        return;
        }

    System.out.println("POP3 NOOP succeeded.");
  }
}