This page contains the code for all the other classes in
the MailClient lab: MailClient.java, Message.java,
and Envelope.java. All of these classes will require
modification in order to handle the actual project specifications.
import java.io.*;
import java.net.*;
import java.awt.*;
import java.awt.event.*;
/* $Id: MailClient.java,v 1.7 1999/07/22 12:07:30 kangasha Exp $ */
/**
* A simple mail client with a GUI for sending mail.
*
* @author Jussi Kangasharju
*/
public class MailClient extends Frame {
/* The stuff for the GUI. */
private Button btSend = new Button("Send");
private Button btClear = new Button("Clear");
private Button btQuit = new Button("Quit");
private Label serverLabel = new Label("Local mailserver:");
private TextField serverField = new TextField("", 40);
private Label fromLabel = new Label("From:");
private TextField fromField = new TextField("", 40);
private Label toLabel = new Label("To:");
private TextField toField = new TextField("", 40);
private Label subjectLabel = new Label("Subject:");
private TextField subjectField = new TextField("", 40);
private Label messageLabel = new Label("Message:");
private TextArea messageText = new TextArea(10, 40);
/**
* Create a new MailClient window with fields for entering all
* the relevant information (From, To, Subject, and message).
*/
public MailClient() {
super("Java Mailclient");
/* Create panels for holding the fields. To make it look nice,
create an extra panel for holding all the child panels. */
Panel serverPanel = new Panel(new BorderLayout());
Panel fromPanel = new Panel(new BorderLayout());
Panel toPanel = new Panel(new BorderLayout());
Panel subjectPanel = new Panel(new BorderLayout());
Panel messagePanel = new Panel(new BorderLayout());
serverPanel.add(serverLabel, BorderLayout.WEST);
serverPanel.add(serverField, BorderLayout.CENTER);
fromPanel.add(fromLabel, BorderLayout.WEST);
fromPanel.add(fromField, BorderLayout.CENTER);
toPanel.add(toLabel, BorderLayout.WEST);
toPanel.add(toField, BorderLayout.CENTER);
subjectPanel.add(subjectLabel, BorderLayout.WEST);
subjectPanel.add(subjectField, BorderLayout.CENTER);
messagePanel.add(messageLabel, BorderLayout.NORTH);
messagePanel.add(messageText, BorderLayout.CENTER);
Panel fieldPanel = new Panel(new GridLayout(0, 1));
fieldPanel.add(serverPanel);
fieldPanel.add(fromPanel);
fieldPanel.add(toPanel);
fieldPanel.add(subjectPanel);
/* Create a panel for the buttons and add listeners to the
buttons. */
Panel buttonPanel = new Panel(new GridLayout(1, 0));
btSend.addActionListener(new SendListener());
btClear.addActionListener(new ClearListener());
btQuit.addActionListener(new QuitListener());
buttonPanel.add(btSend);
buttonPanel.add(btClear);
buttonPanel.add(btQuit);
/* Add, pack, and show. */
add(fieldPanel, BorderLayout.NORTH);
add(messagePanel, BorderLayout.CENTER);
add(buttonPanel, BorderLayout.SOUTH);
pack();
show();
}
static public void main(String argv[]) {
new MailClient();
}
/* Handler for the Send-button. */
class SendListener implements ActionListener {
public void actionPerformed(ActionEvent event) {
System.out.println("Sending mail");
/* Check that we have the local mailserver */
if ((serverField.getText()).equals("")) {
System.out.println("Need name of local mailserver!");
return;
}
/* Check that we have the sender and recipient. */
if((fromField.getText()).equals("")) {
System.out.println("Need sender!");
return;
}
if((toField.getText()).equals("")) {
System.out.println("Need recipient!");
return;
}
/* Create the message */
Message mailMessage = new Message(fromField.getText(),
toField.getText(),
subjectField.getText(),
messageText.getText());
/* Check that the message is valid, i.e., sender and
recipient addresses look ok. */
if(!mailMessage.isValid()) {
return;
}
/* Create the envelope, open the connection and try to send
the message. */
Envelope envelope;
try {
envelope = new Envelope(mailMessage,
serverField.getText());
} catch (UnknownHostException e) {
/* If there is an error, do not go further */
return;
}
try {
SMTPConnection connection = new SMTPConnection(envelope);
connection.send(envelope);
connection.close();
} catch (IOException error) {
System.out.println("Sending failed: " + error);
return;
}
System.out.println("Mail sent succesfully!");
}
}
/* Clear the fields on the GUI. */
class ClearListener implements ActionListener {
public void actionPerformed(ActionEvent e) {
System.out.println("Clearing fields");
fromField.setText("");
toField.setText("");
subjectField.setText("");
messageText.setText("");
}
}
/* Quit. */
class QuitListener implements ActionListener {
public void actionPerformed(ActionEvent e) {
System.exit(0);
}
}
}
import java.util.*;
import java.text.*;
/* $Id: Message.java,v 1.5 1999/07/22 12:10:57 kangasha Exp $ */
/**
* Mail message.
*
* @author Jussi Kangasharju
*/
public class Message {
/* The headers and the body of the message. */
public String Headers;
public String Body;
/* Sender and recipient. With these, we don't need to extract them
from the headers. */
private String From;
private String To;
/* To make it look nicer */
private static final String CRLF = "\r\n";
/* Create the message object by inserting the required headers from
RFC 5322 (From, To, Date). */
public Message(String from, String to, String subject, String text) {
/* Remove whitespace */
From = from.trim();
To = to.trim();
Headers = "From: " + From + CRLF;
Headers += "To: " + To + CRLF;
Headers += "Subject: " + subject.trim() + CRLF;
/* The RFC 5322-required format. */
SimpleDateFormat format =
new SimpleDateFormat("EEE, dd MMM yyyy HH:mm:ss Z");
String dateString = format.format(new Date());
Headers += "Date: " + dateString + CRLF;
Body = text;
}
/* Two functions to access the sender and recipient. */
public String getFrom() {
return From;
}
public String getTo() {
return To;
}
/* Check whether the message is valid. In other words, check that
both sender and recipient contain only one @-sign. */
public boolean isValid() {
int fromat = From.indexOf('@');
int toat = To.indexOf('@');
if(fromat < 1 || (From.length() - fromat) <= 1) {
System.out.println("Sender address is invalid");
return false;
}
if(toat < 1 || (To.length() - toat) <= 1) {
System.out.println("Recipient address is invalid");
return false;
}
if(fromat != From.lastIndexOf('@')) {
System.out.println("Sender address is invalid");
return false;
}
if(toat != To.lastIndexOf('@')) {
System.out.println("Recipient address is invalid");
return false;
}
return true;
}
/* For printing the message. */
public String toString() {
String res;
res = Headers + CRLF;
res += Body;
return res;
}
}
import java.io.*;
import java.net.*;
import java.util.*;
/* $Id: Envelope.java,v 1.8 1999/09/06 16:43:20 kangasha Exp $ */
/**
* SMTP envelope for one mail message.
*
* @author Jussi Kangasharju
*/
public class Envelope {
/* SMTP-sender of the message (in this case, contents of From-header. */
public String Sender;
/* SMTP-recipient, or contents of To-header. */
public String Recipient;
/* Target MX-host */
public String DestHost;
public InetAddress DestAddr;
/* The actual message */
public Message Message;
/* Create the envelope. */
public Envelope(Message message, String localServer)
throws UnknownHostException {
/* Get sender and recipient. */
Sender = message.getFrom();
Recipient = message.getTo();
/* Get message. We must escape the message to make sure that
there are no single periods on a line. This would mess up
sending the mail. */
Message = escapeMessage(message);
/* Take the name of the local mailserver and map it into an
* InetAddress */
DestHost = localServer;
try {
DestAddr = InetAddress.getByName(DestHost);
} catch (UnknownHostException e) {
System.out.println("Unknown host: " + DestHost);
System.out.println(e);
throw e;
}
return;
}
/* Escape the message by doubling all periods at the beginning of
a line. */
private Message escapeMessage(Message message) {
String escapedBody = "";
String token;
StringTokenizer parser = new StringTokenizer(message.Body, "\n", true);
while(parser.hasMoreTokens()) {
token = parser.nextToken();
if(token.startsWith(".")) {
token = "." + token;
}
escapedBody += token;
}
message.Body = escapedBody;
return message;
}
/* For printing the envelope. Only for debug. */
public String toString() {
String res = "Sender: " + Sender + '\n';
res += "Recipient: " + Recipient + '\n';
res += "MX-host: " + DestHost + ", address: " + DestAddr + '\n';
res += "Message:" + '\n';
res += Message.toString();
return res;
}
}