User authentication in Java using the IMAP or SMTP protocols

Recently, a couple of students have asked me the same question:

“I need to authenticate users (other students) in my diploma thesis application with their faculty credentials. Is there a way to do this?”

The faculty student server (i.e. www.scs.ubbcluj.ro) offers two public services: IMAP (on TCP port 993) and SMTP (on TCP port 465). You can use either of these two services to authenticate a user. Just be sure you have the JavaMail jar in your classpath. Since April 2017 the JavaMail API is available as an open source project on GitHub.

Here is a sample piece of code, just pass the username and the password as command line parameters.

import java.util.Properties;
import javax.mail.internet.*;
import javax.mail.*;

public class JavaMailAuthentication {

    public static void main(String[] args) throws Exception {

        String host = "example.com"; // replace example.com with your own host
        Properties props = System.getProperties();
        props.put("mail.store.protocol", "imaps");
        props.put("mail.imaps.port", 993);
        props.put("mail.imaps.host", host);

        javax.mail.Session mailSession = javax.mail.Session.getInstance(props, null);
        Store store = mailSession.getStore();
        try {
            store.connect(host, 993, args[0], args[1]);
            System.out.println("Password is ok");
        } catch (Exception e) {
            System.out.println("Password is not ok");
        }
    }

}

import java.util.Properties;

import javax.mail.internet.*;

import javax.mail.*;

public class JavaMailAuthentication {

public static void main(String[] args) throws Exception {

String host = "example.com"; // replace example.com with your own host

Properties props = System.getProperties();

props.put("mail.store.protocol", "imaps");

props.put("mail.imaps.port", 993);

props.put("mail.imaps.host", host);

javax.mail.Session mailSession = javax.mail.Session.getInstance(props, null);

Store store = mailSession.getStore();

try {

store.connect(host, 993, args[0], args[1]);

System.out.println("Password is ok");

} catch (Exception e) {

System.out.println("Password is not ok");

}

Darius Bufnea