Mail.java

Below is the syntax highlighted version of Mail.java from §8.4 Operating Systems.

/******************************************************************************
 *  Compilation:  javac Mail.java
 *  Execution:    java Mail
 *
 *  Sends email to wayne@cs.princeton.edu addressed from nobody@cnn.com
 *  according to the Simple Mail Transfer Protocol (SMTP).
 *
 *  DO NOT USE this program unless you have permission from the
 *  person receiving the email.
 *
 *  % java Mail
 *
 *  Replace "smtp.princeton.edu" with your local mail server in the code below.
 *
 *  % telnet smtp.princeton.edu 25
 *  HELO localhost
 *  MAIL FROM: nobody@cnn.com
 *  RCPT TO: support@about.com
 *  DATA
 *  Message-ID: <19970817184815.33912@princeton.edu>
 *  Date: Sun, 17 Aug 1997 18:48:15 +0200
 *  From: Nobody <nobody@cnn.com>
 *  To: Kevin Wayne <wayne@cs.princeton.edu>
 *  X-Mailer: Spam Mailer X
 *  Hello, how are you?
 *  This is the body of the message.
 *  .
 *  quit
 *
 ******************************************************************************/

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

public class Mail {
    public static void main(String[] args) throws Exception {

        Socket socket       = new Socket("smtp.princeton.edu", 25);
        BufferedReader in   = new BufferedReader(new InputStreamReader(socket.getInputStream()));
        PrintWriter out     = new PrintWriter(socket.getOutputStream(), true);

        // the return path
        out.println("HELO localhost");
        StdOut.println(in.readLine());

        out.println("MAIL From: nobody@cnn.com");
        StdOut.println(in.readLine());

        // send to this address
        out.println("RCPT To: wayne@cs.princeton.edu");
        StdOut.println(in.readLine());

        out.println("DATA");
        StdOut.println(in.readLine());

        // write message, and end with a . on a line by itself
//        out.println("Message-ID: <19970817184815.33912@princeton.edu>");
        out.println("Date: Wed, 27 Aug 2003 11:48:15 -0400");
        out.println("From: Nobody Here <nobody@cnn.com>");
        out.println("Subject: Just wanted to say hi");
        out.println("To: wayne@cs.princeton.edu");
        out.println("X-Mailer: Spam Mailer X");
        out.println("This is the message body.");
        out.println("Here is a second line.");
        out.println(".");
        StdOut.println(in.readLine());

        // clean up
        out.close();
        in.close();
        socket.close();
    }
}