(Java) Download POP3 Email using UIDLs

Demonstrates how to download POP3 email by first getting the complete set of UIDLs and then downloading email by calling FetchEmail for each UIDL. This is equivalent to calling CopyMail, except your application can process each email as it arrives instead of waiting for the entire bundle to be downloaded. Also, it's better protection against potential out-of-memory issues if your mailbox has a very large number of messages. There is no performance difference between fetching emails individually vs. calling CopyMail.

Chilkat Java Downloads Java Libs for Windows, MacOS, Linux, Alpine Linux, Solaris Java Libs for Android

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.

    // The mailman object is used for receiving (POP3) 
    // and sending (SMTP) email.
    CkMailMan mailman = new CkMailMan();

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

    // Set the POP3 login/password.
    mailman.put_PopUsername("myLogin");
    mailman.put_PopPassword("myPassword");

    CkStringArray sa = mailman.GetUidls();
    if (mailman.get_LastMethodSuccess() != true) {
        System.out.println(mailman.lastErrorText());
        return;
        }

    int i = 0;
    int n = sa.get_Count();

    String uidl;

    while (i < n) {

        uidl = sa.getString(i);

        CkEmail email = mailman.FetchEmail(uidl);
        if (mailman.get_LastMethodSuccess() != true) {
            System.out.println(mailman.lastErrorText());

            return;
            }

        System.out.println("From: " + email.ck_from());
        System.out.println("Subject: " + email.subject());

        i = i+1;
        }

    mailman.Pop3EndSession();
  }
}