gistfile1.java

import javax.mail.Session;
import javax.mail.Transport;
import javax.mail.internet.InternetAddress;
import javax.mail.internet.MimeMessage;
import java.util.Properties;

public class SimpleMail {
    private static String HOST = "smtp.sendgrid.net";
    private static String USER = "your_isername_here";
    private static String PASSWORD = "your_password_here";
    private static String PORT = "465";
    private static String FROM = "[email protected]";
    private static String TO = "[email protected]";

    private static String STARTTLS = "true";
    private static String AUTH = "true";
    private static String DEBUG = "true";
    private static String SOCKET_FACTORY = "javax.net.ssl.SSLSocketFactory";

    public static void main(String[] args) throws Exception {
        new SimpleMail().test();
    }

    public void test() throws Exception {
        Properties props = new Properties();
        props.put("mail.smtp.host", HOST);
        props.put("mail.smtp.port", PORT);
        props.put("mail.smtp.user", USER);

        props.put("mail.smtp.auth", AUTH);
        props.put("mail.smtp.starttls.enable", STARTTLS);
        props.put("mail.smtp.debug", DEBUG);

        props.put("mail.smtp.socketFactory.port", PORT);
        props.put("mail.smtp.socketFactory.class", SOCKET_FACTORY);
        props.put("mail.smtp.socketFactory.fallback", "false");

        Session session = Session.getDefaultInstance(props, null);

        //Construct the mail message
        MimeMessage message = new MimeMessage(session);
        message.setText("body text");
        message.setSubject("subject");
        message.setFrom(new InternetAddress(FROM));
        message.addRecipient(MimeMessage.RecipientType.TO, new InternetAddress(TO));
        message.saveChanges();

        //Use Transport to deliver the message
        Transport transport = session.getTransport("smtp");
        transport.connect(HOST, USER, PASSWORD);
        transport.sendMessage(message, message.getAllRecipients());
        transport.close();

    }
}