Writing Simple Email Clients in Java

• Email Using Sockets

• Email using the JavaMail API

Email Using Sockets (Linden Chapter 17)

// See page 571 of Linden's Just Java Fifth Edition

import java.io.*;import java.net.*;

public class SimpleEmailClient {

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

Socket sock; DataInputStream dis; PrintStream ps;

// open a socket to an email server on port 25 sock = new Socket("cyrus.andrew.cmu.edu",25);

dis = new DataInputStream(sock.getInputStream()); ps = new PrintStream(sock.getOutputStream());

// talk email ps.println("mail from: mm6@andrew.cmu.edu"); System.out.println(dis.readLine());

String Addressee = "mm6@andrew.cmu.edu"; ps.println("rcpt to: " + Addressee);

System.out.println(dis.readLine());

ps.println("data"); System.out.println(dis.readLine());

ps.println("A message sent by a Java client using sockets"); ps.println(".");

System.out.println(dis.readLine());

ps.flush(); sock.close(); }}

Output Echos from Cyrus

D:\McCarthy\www\95-713\JavaMail>java SimpleEmailClient220-mail-fe2.andrew.cmu.edu ESMTP Sendmail 8.12.3.Beta2/8.12.3.Beta2220-Mis-identifing the sender of mail is an abuse of computing facilites.220 ESMTP spoken here250 2.1.0 mm6@andrew.cmu.edu... Sender ok

Using JavaMail// A simple example using JavaMailimport java.io.*;import java.net.InetAddress;import java.util.Properties;import java.util.Date;

import javax.mail.*;import javax.mail.internet.*;

public class Mailer {

String to, from, msg;

public Mailer(String to, String from, String msg) {

this.to = to; this.from = from; this.msg = msg; }

public void send() { Session s = createSession(); try {

Message mess = createMessage(s, msg); Transport.send(mess);

} catch(MessagingException e) {

System.out.println("Messaging Exception: "+e); }

catch(Exception e ) { System.out.println("Exception thrown" + e); }

} private Session createSession() {

Properties p = System.getProperties();p.setProperty("mail.transport.protocol", "smtp");p.setProperty("mail.smtp.host","cyrus.andrew.cmu.edu");Session sess = Session.getDefaultInstance(p);return sess;

}

private Message createMessage(Session sess, String msg)throws MessagingException{

Message mess = new MimeMessage(sess);mess.setFrom(new InternetAddress(from));

mess.setRecipients(Message.RecipientType.TO,InternetAddress.parse(to, false));

mess.setSubject("Warning");mess.setText(msg);mess.setSentDate(new Date());

return mess;}

public static void main(String a[]) { Mailer mailman = new Mailer("mm6@andrew.cmu.edu", "mccarthy@cs.pitt.edu", "It's hot"); mailman.send();

}}

Installation Instructions

1. Download the JavaMail API Implementation Version 1.3ea

2. Download the JavaBeans Activation Framework 1.0.2ea

3. Unzip both files.4. Add the following files to your classpath:

– mail.jar (JavaMail)– activation.jar (JAF file)

Visit http://java.sun.com/products/javamail