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Java

POP3 GMail XOAUTH2 Authentication

See more GMail SMTP/IMAP/POP Examples

Demonstrates using OAuth2 authentication with pop.gmail.com.

Note: This example requires Chilkat v9.5.0.83 or greater.

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Chilkat2 Java
import com.chilkatsoft.chilkat2.ChilkatException;
import com.chilkatsoft.chilkat2.JsonObject;
import com.chilkatsoft.chilkat2.MailMan;

public class ChilkatExample {

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

        MailMan mailman = new MailMan();

        mailman.setMailHost("pop.gmail.com");
        mailman.setMailPort(995);
        mailman.setPopSsl(true);

        mailman.setPopUsername("my_account@gmail.com");

        // If using OAuth2 authentication, leave the password empty.
        mailman.setPopPassword("");

        // Load our previously obtained OAuth2 access token.
        // See Getting a GMail POP3 OAuth2 Access Token
        JsonObject jsonToken = new JsonObject();
        try {
            jsonToken.loadFile("qa_data/tokens/gmail_pop3.json");

            mailman.setOAuth2AccessToken(jsonToken.stringOf("access_token"));

            // Make the TLS connection to the POP3 server.
            mailman.pop3Connect();

            // Authenticate..
            mailman.pop3Authenticate();
        } catch (ChilkatException e) {
            System.out.println(e.getLastErrorText());
            return;
        }

        // Find out how many emails are on the server..
        int numEmails = mailman.checkMail();
        if (numEmails < 0) {
            System.out.println(mailman.getLastErrorText());
            return;
        }

        // Examine the POP3 session log:
        System.out.println(mailman.getPop3SessionLog());

        // The POP3 session log will look something like this:

        // **** Connected to pop.gmail.com:995
        // < +OK Gpop ready for requests from 87.9.200.42 l16mb86351205iok
        // > AUTH XOAUTH2 dXNlcj1....VaMDJFAQE=
        // < +OK Welcome.
        // > STAT
        // < +OK 301 1627357
        //
        // -- Finished.

        // End the POP3 session and close the connection to the GMail server.
        try {
            mailman.pop3EndSession();
        } catch (ChilkatException e) {
            System.out.println(e.getLastErrorText());
            return;
        }

        System.out.println("-- Finished.");
    }
}