startActivity(new Intent(anotherClass.this, SendMail.class));

public void loginAs()
{
SendMail class2 = new SendMail();
class2.doSomething();
}

public static void doSomething() {
    SendMail.main(new String[] {"main"});
}

"Oops something has gone pearshaped!"

07-20 16:32:29.507  11953-11953/seatme.camaleonpos.com.seatme I/System.out﹕ android.os.NetworkOnMainThreadException

import...

public class SendMail extends Object {

public static void doSomething(String sUser, String sPass) {
SendMail.main(new String[] {"main"})
}

public static void main(String [] args)
{
    for (String s : args)
        System.out.println(s);
    try{
        Properties props = new Properties();
        props.put("mail.smtp.host", "smtp.gmail.com"); // for gmail use smtp.gmail.com
        props.put("mail.smtp.auth", "true");
        props.put("mail.debug", "true");
        props.put("mail.smtp.starttls.enable", "true");
        props.put("mail.smtp.port", "465");
        props.put("mail.smtp.socketFactory.port", "465");
        props.put("mail.smtp.socketFactory.class", "javax.net.ssl.SSLSocketFactory");
        props.put("mail.smtp.socketFactory.fallback", "false");
        Session mailSession = Session.getInstance(props, new javax.mail.Authenticator() {
            protected PasswordAuthentication getPasswordAuthentication() {
                return new PasswordAuthentication("foo@gmail.com", "foo"); } });
        mailSession.setDebug(true); // Enable the debug mode
        Message msg = new MimeMessage( mailSession );
        //--[ Set the FROM, TO, DATE and SUBJECT fields
        msg.setFrom( new InternetAddress( "foo@gmail.com " ) );
        msg.setRecipients( Message.RecipientType.TO,InternetAddress.parse("1111111111@messaging.sprintpcs.com") );
        msg.setSentDate( new Date());
        msg.setSubject( "Hello World!" );
        //--[ Create the body of the mail
        msg.setText( "Hello from my first e-mail sent with JavaMail" );
        //--[ Ask the Transport class to send our mail message
        Transport.send( msg );
    }catch(Exception E){
        System.out.println( "Oops something has gone pearshaped!");
        System.out.println( E );
        return;
    }
}
}