Java/Network Protocol/SMTP

A Thin SMTP Client

 
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.net.Socket;
import java.text.DateFormat;
import java.util.Date;
import java.util.Locale;
public class Main {
  public static void main(String[] args) throws Exception {
    String host = "host";
    int port = 25;
    String from = "from@from.net";
    String toAddr = "to@to.net";

    Socket servSocket = new Socket(host, port);
    DataOutputStream os = new DataOutputStream(servSocket.getOutputStream());
    DataInputStream is = new DataInputStream(servSocket.getInputStream());
    if (servSocket != null && os != null && is != null) {
      os.writeBytes("HELO\r\n");
      os.writeBytes("MAIL From:" + from + " \r\n");
      os.writeBytes("RCPT To:" + toAddr + "\r\n");
      os.writeBytes("DATA\r\n");
      os.writeBytes("X-Mailer: Java\r\n");
      os.writeBytes("DATE: " + DateFormat.getDateInstance(DateFormat.FULL, Locale.US).format(new Date()) + "\r\n");
      os.writeBytes("From:" + from + "\r\n");
      os.writeBytes("To:" + toAddr + "\r\n");
    }
    os.writeBytes("Subject:\r\n");
    os.writeBytes("body\r\n");
    os.writeBytes("\r\n.\r\n");
    os.writeBytes("QUIT\r\n");
    String responseline;
    while ((responseline = is.readUTF()) != null) { 
      if (responseline.indexOf("Ok") != -1)
        break;
    }
  }
}

SMTP package to send a message to the specified recipients

 
/*
 * Copyright 2001-2005 The Apache Software Foundation
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package examples;
import java.io.BufferedReader;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.io.Writer;
import java.util.Enumeration;
import java.util.Vector;
import org.apache.rumons.net.io.Util;
import org.apache.rumons.net.smtp.SMTPClient;
import org.apache.rumons.net.smtp.SMTPReply;
import org.apache.rumons.net.smtp.SimpleSMTPHeader;
/***
 * This is an example program using the SMTP package to send a message
 * to the specified recipients.  It prompts you for header information and
 * a filename containing the message.
 * <p>
 ***/
public class mail
{
    public final static void main(String[] args)
    {
        String sender, recipient, subject, filename, server, cc;
        Vector ccList = new Vector();
        BufferedReader stdin;
        FileReader fileReader = null;
        Writer writer;
        SimpleSMTPHeader header;
        SMTPClient client;
        Enumeration en;
        if (args.length < 1)
        {
            System.err.println("Usage: mail smtpserver");
            System.exit(1);
        }
        server = args[0];
        stdin = new BufferedReader(new InputStreamReader(System.in));
        try
        {
            System.out.print("From: ");
            System.out.flush();
            sender = stdin.readLine();
            System.out.print("To: ");
            System.out.flush();
            recipient = stdin.readLine();
            System.out.print("Subject: ");
            System.out.flush();
            subject = stdin.readLine();
            header = new SimpleSMTPHeader(sender, recipient, subject);

            while (true)
            {
                System.out.print("CC <enter one address per line, hit enter to end>: ");
                System.out.flush();
                // Of course you don"t want to do this because readLine() may be null
                cc = stdin.readLine().trim();
                if (cc.length() == 0)
                    break;
                header.addCC(cc);
                ccList.addElement(cc);
            }
            System.out.print("Filename: ");
            System.out.flush();
            filename = stdin.readLine();
            try
            {
                fileReader = new FileReader(filename);
            }
            catch (FileNotFoundException e)
            {
                System.err.println("File not found. " + e.getMessage());
            }
            client = new SMTPClient();
            client.addProtocolCommandListener(new PrintCommandListener(
                                                  new PrintWriter(System.out)));
            client.connect(server);
            if (!SMTPReply.isPositiveCompletion(client.getReplyCode()))
            {
                client.disconnect();
                System.err.println("SMTP server refused connection.");
                System.exit(1);
            }
            client.login();
            client.setSender(sender);
            client.addRecipient(recipient);
            en = ccList.elements();
            while (en.hasMoreElements())
                client.addRecipient((String)en.nextElement());
            writer = client.sendMessageData();
            if (writer != null)
            {
                writer.write(header.toString());
                Util.copyReader(fileReader, writer);
                writer.close();
                client.rupletePendingCommand();
            }
            fileReader.close();
            client.logout();
            client.disconnect();
        }
        catch (IOException e)
        {
            e.printStackTrace();
            System.exit(1);
        }
    }
}

SMTP talker class

 
/*
 * Copyright (c) Ian F. Darwin, http://www.darwinsys.ru/, 1996-2002.
 * All rights reserved. Software written by Ian F. Darwin and others.
 * $Id: LICENSE,v 1.8 2004/02/09 03:33:38 ian Exp $
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS""
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 * 
 * Java, the Duke mascot, and all variants of Sun"s Java "steaming coffee
 * cup" logo are trademarks of Sun Microsystems. Sun"s, and James Gosling"s,
 * pioneering role in inventing and promulgating (and standardizing) the Java 
 * language and environment is gratefully acknowledged.
 * 
 * The pioneering role of Dennis Ritchie and Bjarne Stroustrup, of AT&T, for
 * inventing predecessor languages C and C++ is also gratefully acknowledged.
 */
///
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintStream;
import java.net.ConnectException;
import java.net.NoRouteToHostException;
import java.net.Socket;
import java.net.UnknownHostException;
import java.util.StringTokenizer;
/**
 * SMTP talker class, usable standalone (as a SendMail(8) backend) or inside
 * applications such as JabaDex that need to send mail..
 * 
 * OBSOLETE!! Use javax.mail instead, now that it"s available!
 * 
 * Needs more parameterization - bit of a hack to start. Should use same
 * interface as Mailer (subclass, and override doSend()).
 * 
 * @author Ian Darwin
 * @version $Id: SmtpTalk.java,v 1.10 2002/10/26 13:53:45 ian Exp $
 */
public class SmtpTalk {
  BufferedReader is;
  PrintStream os;
  private boolean debug = true;
  private String host;
  /**
   * A simple main program showing the class in action.
   * 
   * TODO generalize to accept From arg, read msg on stdin
   */
  public static void main(String[] argv) {
    if (argv.length != 2) {
      System.err.println("Usage: java SmtpTalk host user");
      System.exit(1);
    }
    try {
      SmtpTalk st = new SmtpTalk(argv[0]);
      System.out.println("SMTP Talker ready");
      st.converse("MAILER-DAEMON@daroad.darwinsys.ru", argv[1],
          "Test message", "Hello there");
    } catch (Exception ig) {
      System.err.println(ig.getMessage());
      System.exit(0);
    }
  }
  /**
   * Constructor taking a server hostname as argument.
   */
  SmtpTalk(String server) throws Exception {
    host = server;
    try {
      Socket s = new Socket(host, 25);
      is = new BufferedReader(new InputStreamReader(s.getInputStream()));
      os = new PrintStream(s.getOutputStream());
    } catch (NoRouteToHostException e) {
      die( "No route to host " + host);
    } catch (ConnectException e) {
      die("Connection Refused by " + host);
    } catch (UnknownHostException e) {
      die("Unknown host " + host);
    } catch (IOException e) {
      die( "I/O error setting up socket streams\n" + e);
    }
  }
  /** Send a command with an operand */
  protected void send_cmd(String cmd, String oprnd) {
    send_cmd(cmd + " " + oprnd);
  }
  /* Send a command with no operand */
  protected void send_cmd(String cmd) {
    if (debug)
      System.out.println(">>> " + cmd);
    os.print(cmd + "\r\n");
  }
  /** Send_text sends the body of the message. */
  public void send_text(String text) {
    os.print(text + "\r\n");
  }
  /** Expect (read and check for) a given reply */
  protected boolean expect_reply(String rspNum) throws Exception {
    String s = null;
    try {
      s = is.readLine();
    } catch (IOException e) {
      die( "I/O error reading from host " + host + " " + e);
    }
    if (debug)
      System.out.println("<<< " + s);
    return s.startsWith(rspNum + " ");
  }
  /**
   * Convenience routine to print message & exit, like K&P error(), perl
   * die(), ...
   * 
   * @param ret
   *            Numeric value to pass back
   * @param msg
   *            Error message to be printed on stdout.
   */
  protected void die(String msg) throws Exception {
    throw new Exception( msg);
  }
  /**
   * send one Mail message to one or more recipients via smtp to server
   * "host".
   */
  public void converse(String sender, String recipients, String subject,
      String body) throws Exception {
    if (!expect_reply("220"))
      die("did not get SMTP greeting");
    send_cmd("HELO", "darwinsys.ru");
    if (!expect_reply("250"))
      die("did not ack our HELO");
    send_cmd("MAIL", "From:<" + sender + ">"); // no spaces!
    if (!expect_reply("250"))
      die("did not ack our MAIL command");
    StringTokenizer st = new StringTokenizer(recipients);
    while (st.hasMoreTokens()) {
      String r = st.nextToken();
      send_cmd("RCPT", "To:<" + r + ">");
      if (!expect_reply("250"))
        die("didn"t ack RCPT " + r);
    }
    send_cmd("DATA");
    if (!expect_reply("354"))
      die("did not want our DATA!");
    send_text("From: " + sender);
    send_text("To: " + recipients);
    send_text("Subject: " + subject);
    send_text("");
    send_text(body + "\r");
    send_cmd(".");
    if (!expect_reply("250"))
      die("Mail not accepted");
    send_cmd("QUIT");
    if (!expect_reply("221"))
      die("Other end not closing down");
  }
}