Mail program timing out to smtp.gmail.com

[Jon Camilleri]

Is it possible to update this code snippet, in order to reflect the authentication required by Gmail. When I run this program using smtp.gmail.com as an SMTP server, an error is reading java.net.ConnectException

/**
@author Cay Horstmann
@version 1.10 2004-08-03
*/
import java.awt.*;
import java.awt.event.*;
import java.util.*;
import java.net.*;
import java.io.*;
import javax.swing.*;
/**
This program shows how to use sockets to send plain text
mail messages.
*/
public class MailTest
{
public static void main(String[] args)
{
JFrame frame = new MailTestFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
}
}
/**
The frame for the mail GUI.
*/
class MailTestFrame extends JFrame
{
public MailTestFrame()
{
setSize(DEFAULT_WIDTH, DEFAULT_HEIGHT);
setTitle("MailTest");
setLayout(new GridBagLayout());
// we use the GBC convenience class of Core Java Volume 1 Chapter 9
add(new JLabel("From:"), new GBC(0, 0).setFill(GBC.HORIZONTAL));
from = new JTextField(20);
add(from, new GBC(1, 0).setFill(GBC.HORIZONTAL).setWeight(100, 0));
add(new JLabel("To:"), new GBC(0, 1).setFill(GBC.HORIZONTAL));
to = new JTextField(20);
add(to, new GBC(1, 1).setFill(GBC.HORIZONTAL).setWeight(100, 0));
add(new JLabel("SMTP server:"), new GBC(0, 2).setFill(GBC.HORIZONTAL));
smtpServer = new JTextField(20);
add(smtpServer, new GBC(1, 2).setFill(GBC.HORIZONTAL).setWeight(100, 0));
message = new JTextArea();
add(new JScrollPane(message), new GBC(0, 3, 2, 1).setFill(GBC.BOTH).setWeight(100, 100));
comm = new JTextArea();
add(new JScrollPane(comm), new GBC(0, 4, 2, 1).setFill(GBC.BOTH).setWeight(100, 100));
JPanel buttonPanel = new JPanel();
add(buttonPanel, new GBC(0, 5, 2, 1));
JButton sendButton = new JButton("Send");
buttonPanel.add(sendButton);
sendButton.addActionListener(new
ActionListener()
{
public void actionPerformed(ActionEvent event)
{
new Thread(new
Runnable()
{
public void run()
{
comm.setText("");
sendMail();
}
}).start();
}
});
}
/**
Sends the mail message that has been authored in the GUI.
*/
public void sendMail()
{
try
{
Socket s = new Socket(smtpServer.getText(), 25);
InputStream inStream = s.getInputStream();
OutputStream outStream = s.getOutputStream();
in = new Scanner(inStream);
out = new PrintWriter(outStream, true /* autoFlush */);
String hostName = InetAddress.getLocalHost().getHostName();
receive();
send("HELO " + hostName);
receive();
send("MAIL FROM: <" + from.getText() + ">");
receive();
send("RCPT TO: <" + to.getText() + ">");
receive();
send("DATA");
receive();
send(message.getText());
send(".");
receive();
s.close();
}
catch (IOException e)
{
comm.append("Error: " + e);
}
}
/**
Sends a string to the socket and echoes it in the
comm text area.
@param s the string to send.
*/
public void send(String s) throws IOException
{
comm.append(s);
comm.append("\n");
out.print(s.replaceAll("\n", "\r\n"));
out.print("\r\n");
out.flush();
}
/**
Receives a string from the socket and displays it
in the comm text area.
*/
public void receive() throws IOException
{
if (in.hasNextLine());
{
String line = in.nextLine();
comm.append(line);
comm.append("\n");
}
}
private Scanner in;
private PrintWriter out;
private JTextField from;
private JTextField to;
private JTextField smtpServer;
private JTextArea message;
private JTextArea comm;
public static final int DEFAULT_WIDTH = 300;
public static final int DEFAULT_HEIGHT = 300;
}

Source Core Java Volume 2 (7th Edition)

Related links
1. Configuring other email clients (Gmail).
2. RFC 2183, updated by RFC 2184, and, RFC 2231.

[Rob Spoor]

Don't manually connect to an SMTP server, but use JavaMail instead. It's designed for this kind of thing, and if you search a bit you'll find plenty of examples about getting JavaMail to connect to Google.