// package ...;

import java.util.*;
import java.io.*;
import javax.mail.*;
import javax.mail.internet.*;
import javax.activation.*;


public class Emailer
{
  private String smptServer = "";

  public void setSMTP_Server(String server)
  {
    smptServer = server;
  }

  public String getSMTP_Server()
  {
    return smptServer;
  }

  public void enviarEmail ( String efrom, String eto, String esubject, String emsgtext) throws IOException
  {
    enviarEmail (efrom, eto, esubject, emsgtext, null, null);
  }

  public void enviarEmail ( String efrom, String eto, String esubject, String emsgtext, String contenidoAttach, String nombreFicheroAttach) throws IOException
  {
      // Enviar e-mail

      Properties props = new Properties();
      props.put("mail.smtp.host", smptServer);

      Session session = Session.getDefaultInstance(props, null);

      String from = efrom;
      String to =  eto;
      String subject = esubject;
      String msgText = emsgtext;

      try
      {
          // create a message
          Message msg = new MimeMessage(session);
          msg.setFrom(new InternetAddress(from));
          InternetAddress[] address = {new InternetAddress(to)};
          msg.setRecipients(Message.RecipientType.TO, address);
          msg.setSubject(subject);
          msg.setSentDate(new Date());
          // If the desired charset is known, you can use
          // setText(text, charset)
          msg.setText(msgText);

          if (contenidoAttach != null && nombreFicheroAttach != null)
          {
            // Instantiate a Multipart object
            ByteArrayInputStream bin = new ByteArrayInputStream(contenidoAttach.getBytes());
            MimeBodyPart b1 = new MimeBodyPart(bin);
            b1.setFileName(nombreFicheroAttach);
            MimeMultipart mp = new MimeMultipart();
            mp.addBodyPart(b1);
            msg.setContent(mp); // add Multipart
          }
          Transport.send(msg);
      }
      catch (MessagingException mex)
      {
          System.out.println("\n--Capturada en Emailer.java");

          mex.printStackTrace();
          System.out.println();
          Exception ex = mex;
          do
          {
            if (ex instanceof SendFailedException)
            {
              SendFailedException sfex = (SendFailedException)ex;
              Address[] invalid = sfex.getInvalidAddresses();
              if (invalid != null)
              {
                System.out.println("    ** Invalid Addresses");
                if (invalid != null)
                {
                  for (int i = 0; i < invalid.length; i++)
                  System.out.println("         " + invalid[i]);
                }
              }
              Address[] validUnsent = sfex.getValidUnsentAddresses();
              if (validUnsent != null)
              {
                System.out.println("    ** ValidUnsent Addresses");
                if (validUnsent != null)
                {
                  for (int i = 0; i < validUnsent.length; i++)
                    System.out.println("         "+validUnsent[i]);
                }
              }
              Address[] validSent = sfex.getValidSentAddresses();
              if (validSent != null)
              {
                System.out.println("    ** ValidSent Addresses");
                if (validSent != null)
                {
                  for (int i = 0; i < validSent.length; i++)
                    System.out.println("         "+validSent[i]);
                }
              }
            }
            System.out.println();
         } while ((ex = ((MessagingException)ex).getNextException())!= null);
      }
   }

   /**
     Banco de pruebas.
     Librerias necesarias: mail.jar y activation.jar
     Para comprobar recepción ir a http://mail.bit-net.org:8383
                              Username: apei@bit-net.org
                              Password: apei
   */
   public static void main(String[] args) throws Exception
   {
     Emailer e = new Emailer();
     e.setSMTP_Server("mailhost.terra.es");
     String msg = "Esto es una prueba de Emailer." +
                  "Adiós";

     e.enviarEmail("yo@terra.es", "apei@bit-net.org", "Prueba Emailer", msg);
     System.out.println("Mail enviado. Pulse intro para concluir.");
     System.in.read();
   }
}