(Java) Process Large POP3 Mailbox

Demonstrates how to read email from a mailbox that may contain a large number of emails.

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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();

    mailman.put_MailHost("pop.example.com");

    mailman.put_PopUsername("myLogin");
    mailman.put_PopPassword("myPassword");

    mailman.put_MailPort(995);
    mailman.put_PopSsl(true);

    // Get the list of UIDLs for all emails in the mailbox.
    CkStringArray sa = mailman.GetUidls();
    if (mailman.get_LastMethodSuccess() == false) {
        System.out.println(mailman.lastErrorText());
        return;
        }

    int i;
    int numEmails = sa.get_Count();
    if (numEmails == 0) {
        System.out.println("Mailbox is empty");
        return;
        }

    int chunkSize = 6;

    // Download the emails in chunks of 6 emails each.
    int chunkBeginIdx = 0;
    int chunkEndIdx = chunkSize - 1;
    if (chunkEndIdx >= numEmails) {
        chunkEndIdx = numEmails - 1;
        }

    CkStringArray saChunk = new CkStringArray();
    while ((chunkBeginIdx < numEmails)) {

        System.out.println(chunkBeginIdx + " to " + chunkEndIdx);

        // Build a chunk of UIDLs.
        saChunk.Clear();
        for (i = chunkBeginIdx; i <= chunkEndIdx; i++) {
            saChunk.Append(sa.getString(i));
            }

        // Log the UIDLs in this chunk...
        String chunkStr = saChunk.saveToText();
        System.out.println(chunkStr);

        // Download this chunk of email from the POP3 server.
        CkEmailBundle bundle = mailman.FetchMultiple(saChunk);
        if (mailman.get_LastMethodSuccess() == false) {
            System.out.println(mailman.lastErrorText());
            return;
            }

        System.out.println("Downloaded " + bundle.get_MessageCount() + " emails.");
        System.out.println("----");

        // Process the bundle...
        // (your application's processing code goes here...)

        // Get the next chunk...
        chunkBeginIdx = chunkBeginIdx+chunkSize;
        chunkEndIdx = chunkEndIdx+chunkSize;
        if (chunkEndIdx >= numEmails) {
            chunkEndIdx = numEmails - 1;
            }

        }
  }
}