smtp.java

java开源邮件服务器 smtp pop3

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

/**
 Sends a mail message via the SMTP protocol.
**/

public class smtp
{
    private int    smtpPort = 25;
    private Socket socket;
    private PrintWriter ps;
    private BufferedReader dis;
    private boolean results = false;
    private String  errorResults = "No Error Defined";
    private String  cr = "\r\n";
    private String  thisClass = "(SMTP)";

    /**
     Send a message via SMTP
     @param portNumber The number of the sockets port
     @param smtpServer The server name
     @param toAddress  The address to send the message to
     @param fromAddress The address of the user sending the message
     @param smtpMessage The message to send
    **/


    public smtp( int portNumber,
                 String smtpServer,  String toAddress,
                 String fromAddress, String smtpMessage )
    {
        smtpPort = portNumber;
        send( smtpServer, toAddress, fromAddress, smtpMessage );
    }

    /**
     Send a message via SMTP using the default port.
     @param smtpServer The server name
     @param toAddress  The address to send the message to
     @param fromAddress The address of the user sending the message
     @param smtpMessage The message to send
    **/

    public smtp( String smtpServer,  String toAddress,
                 String fromAddress, String smtpMessage )
    {
        send( smtpServer, toAddress, fromAddress, smtpMessage );
    }

    /**
     Creates an illegal SMTP transaction.
    **/

    public smtp()
    {
    }

    /**
     Returns the results of the transmission
    **/

    public boolean result()
    {
        return results;
    }

    /**
     Returns the error results of the transmission
     **/

    public String errorResult()
    {
        return thisClass + " " + errorResults;
    }



    /**
     Sends a message via SMTP on the specified port.
     @param smtpServer The server name
     @param toAddress  The address to send the message to
     @param fromAddress The address of the user sending the message
     @param smtpMessage The message to send
    **/

    void send( String smtpServer,  String toAddress,
               String fromAddress, String smtpMessage )
    {
        InetAddress rina;
        InetAddress lina;
        results = true; // Assume success

        try
        {
            // Open connection to SMTP server
            socket = new Socket(smtpServer, smtpPort);

            // Send the form contents as a message
            rina = socket.getInetAddress();
            lina = rina.getLocalHost();
            ps  = new PrintWriter(socket.getOutputStream());
            dis = new BufferedReader(new InputStreamReader ( socket.getInputStream()));

            // Send message

            if ( ( sendline( "HELO "       + lina.toString() ) ) &&
                 ( sendline( "MAIL FROM:<" + fromAddress + ">" ) ) &&
                 ( sendline( "RCPT TO:<"   + toAddress + ">" ) ) &&
                 ( sendline( "DATA" ) ) &&
                 ( sendline( smtpMessage ) ) &&
                 ( sendline( "." ) ) &&
                 ( sendline( "QUIT" ) ) )
            {
                results = true; // It is anyway, used for short-circuit
                errorResults = "Delivered to " + toAddress;
            }

            socket.close();
        }
        catch ( Exception ex )
        {
            results      = false;
            errorResults = "Socket exception";

            try
            {
                socket.close();
            }
            catch ( Exception e )
            {
                errorResults = "Could not even close socket exception";
            }
        }
    }


    /**
    Send a line of data to the server, and retrieve the handshake
    */

    boolean sendline( String data ) throws IOException
    {
        ps.print( data + cr );
        ps.flush();
        String s = dis.readLine();

        if ( ! ( ( s.startsWith( "2" ) ) ||
                 ( s.startsWith( "3" ) ) ) )
        {
            results      = false;
            errorResults = s;
        }

        return results;
    }


    static String subnetDomain( String input )
    {
        String here = user( input );
        int    pos  = here.indexOf('%');

        if ( pos == -1 ) // Not found
        {
            return domain( input );
        }

        return here.substring( pos + 1, here.length() );
    }

    static String subnetUser( String input )
    {
        String here = user( input );
        int    pos  = here.indexOf('%');

        if ( pos == -1 ) // Not found
        {
            return user( input );
            //pos = here.length();
        }

        return here.substring( 0, pos );
    }


    static String domain( String input )
    {
        String here = wholeUser( input );
        int    pos  = here.indexOf('@');

        if ( ( pos == -1 ) || ( pos >= ( here.length() - 1 ) ) )
        {
            return "";
        }

        return here.substring( pos + 1, here.length() );
    }

    static String user( String input )
    {
        String here = wholeUser( input );
        int    pos  = here.indexOf('@');

        if ( pos == -1 )
        {
            pos = here.length();
        }

        return here.substring( 0, pos );
    }

    // Returns user name, without the <>s.

    static String wholeUser( String input ) 
    {
        int start = input.indexOf('<') + 1;
        int end   = input.indexOf('>');

        if ( end == -1 ) // Not found
        {
            end = input.length();
        }

        if ( ( input.length() == 0 ) || ( start == end ) )
        {
            return "";
        }

        return input.substring( start, end );
    }
}