Quick walk through the advanced concepts in Java - Part 3 of series

The JavaMail API provides a protocol-independent and platform-independent framework to build messaging and mail applications. The JavaMail API defines classes which represent components of a mail system. JavaMail does not implement an email server instead it allows accessing an email server using a Java API. JavaMail typically includes support for IMAP,SMTP and POP3. The below can be downloaded from below link:

JavaMail (Version 1.5.2)

Download and unzip these files in newly created top level directories.

Set CLASSPATH to add javax.mail.jar.

Send a Simple E-mail using JavaMail API 1.5.2 using SMTP:

A simple e-mail application from machine

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

public class SMTPExample {
	private static final String SMTP_HOST_NAME = "localhost"; //or any other SMTP host
	private static final String SMTP_AUTH_USER = "me@localhost";
	private static final String SMTP_AUTH_PWD = "password";
	private static final String message = "This is a test email";
	private static final String subject = "Email test";
	private static final String from = "me@localhost";

	// recipients email address
	private static final String[] recipients = {
		"you@localhost"
	};

	public static void main(String args[]) throws Exception {
		SendMailUsingAuthentication smtpMailSender = new SendMailUsingAuthentication();
		smtpMailSender.postMail(recipients, subject, message, from);
		System.out.println("Email has been sent successfully");
	}

	public void postMail(String recipients[], String subject,
	String message, String from) throws MessagingException, AuthenticationFailedException {
		boolean debug = false;

		//Set the host smtp address
		Properties props = new Properties();
		props.put("mail.smtp.host", SMTP_HOST_NAME);
		props.put("mail.smtp.auth", "true");
		Authenticator auth = new SMTPAuthenticator();
		Session session = Session.getDefaultInstance(props, auth);
		session.setDebug(debug);
		// Message part
		Message msg = new MimeMessage(session);

		// spcifiy who from this email will be sent from
		InternetAddress addressFrom = new InternetAddress(from);
		msg.setFrom(addressFrom);
                // set who to this email will be sent to 
		InternetAddress[] addressTo = new InternetAddress[recipients.length];
		for (int i = 0; i & lt; recipients.length; i++) {
			addressTo[i] = new InternetAddress(recipients[i]);
		}
		msg.setRecipients(Message.RecipientType.TO, addressTo);

		// Setting the Subject and Content Type
		msg.setSubject(subject);
		msg.setContent(message, "text/plain");
		Transport.send(msg);
	}

	private class SMTPAuthenticator extends javax.mail.Authenticator {
		public PasswordAuthentication getPasswordAuthentication() {
			String username = SMTP_AUTH_USER;
			String password = SMTP_AUTH_PWD;
			return new PasswordAuthentication(username, password);
		}
	}
}

You are also able to send HTML emails or emails with attachments. More on JavaMail can be found on java.net JavaMail project page and the API pages