What is wrong here to send mail in java, I am getting javax.mail.MessagingException

Question

I want to send mails using JAVA,here is the code I written but not working for me. It's throwing exception like this

javax.mail.MessagingException: Could not connect to SMTP host: localhost, port: 25;

My code here:

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

 public class SendEmail  
 {  
 public static void main(String [] args){  
    String to = "to@gmail.com";  
    String from = "from@gmail.com";
    String host = "localhost"; 

  //Get the session object  
  Properties properties = System.getProperties();  
  properties.setProperty("mail.smtp.host", host);  
  Session session = Session.getDefaultInstance(properties);  

  //compose the message  
  try{  
     MimeMessage message = new MimeMessage(session);  
     message.setFrom(new InternetAddress(from));  
        message.addRecipient(Message.RecipientType.TO,
       newInternetAddress(to));  
     message.setSubject("Ping");  
     message.setText("Hello, this is example of sending email  ");  

     // Send message  
     Transport.send(message);  
     System.out.println("message sent successfully....");  

    }catch (MessagingException mex) {mex.printStackTrace();}  
   }  
 }  

Answer 1

you want to send emails using gmail smtp so you must configure it like this

    import java.util.Properties;

    import javax.mail.Message;
    import javax.mail.MessagingException;
    import javax.mail.PasswordAuthentication;
    import javax.mail.Session;
    import javax.mail.Transport;
    import javax.mail.internet.InternetAddress;
    import javax.mail.internet.MimeMessage;

    public class SendeMails {

/***
*    gmail via TLS
*
**/
/*
    public static void main(String[] args) {

        final String username = "username@gmail.com";
        final String password = "password";

        Properties props = new Properties();
        props.put("mail.smtp.auth", "true");
        props.put("mail.smtp.starttls.enable", "true");
        props.put("mail.smtp.host", "smtp.gmail.com");
        props.put("mail.smtp.port", "587");

        Session session = Session.getInstance(props,
          new javax.mail.Authenticator() {
            protected PasswordAuthentication getPasswordAuthentication() {
                return new PasswordAuthentication(username, password);
            }
          });

        try {

            Message message = new MimeMessage(session);
            message.setFrom(new InternetAddress("username@gmail.com"));
            message.setRecipients(Message.RecipientType.TO,
                InternetAddress.parse("to@gmail.com"));
            message.setSubject("Testing Subject");
            message.setText("Dear Mail Crawler,"
                + "\n\n No spam to my email, please!");

            javax.mail.Transport.send(message);

            System.out.println("Done");

        } catch (MessagingException e) {
            throw new RuntimeException(e);
        }
    }
*/  
/***
*    gmail via SSL
*
**/
    public static void main(String[] args) {
        Properties props = new Properties();
        props.put("mail.smtp.host", "smtp.gmail.com");
        props.put("mail.smtp.socketFactory.port", "465");
        props.put("mail.smtp.socketFactory.class",
                "javax.net.ssl.SSLSocketFactory");
        props.put("mail.smtp.auth", "true");
        props.put("mail.smtp.port", "465");

        Session session = Session.getDefaultInstance(props,
            new javax.mail.Authenticator() {
                protected PasswordAuthentication getPasswordAuthentication() {
                    return new PasswordAuthentication("username","password");
                }
            });

        try {

            Message message = new MimeMessage(session);
            message.setFrom(new InternetAddress("from@gmail.com"));
            message.setRecipients(Message.RecipientType.TO,
                    InternetAddress.parse("to@no-spam.com"));
            message.setSubject("Testing Subject");
            message.setText("Dear Mail Crawler," +
                    "\n\n No spam to my email, please!");

            Transport.send(message);

            System.out.println("Done");

        } catch (MessagingException e) {
            throw new RuntimeException(e);
        }
    }
    }

Answer 2

The following code worked for me. And do not forget about

activation.jar , java-mail-1.4.4.jar , javamail-smtp-1.4.2.jar , mail-6.0.0-sources.jar (which i had used)

Code

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

public class Email {

private static String USER_NAME = "username";  // GMail user name (just the part before "@gmail.com")
private static String PASSWORD = "password"; // GMail password

private static String RECIPIENT = "xxxxx@gmail.com";

public static void main(String[] args) {
    String from = USER_NAME;
    String pass = PASSWORD;
    String[] to = { RECIPIENT }; // list of recipient email addresses
    String subject = "Java send mail example";
    String body = "hi ....,!";

    sendFromGMail(from, pass, to, subject, body);
}

private static void sendFromGMail(String from, String pass, String[] to, String subject, String body) {
    Properties props = System.getProperties();
  String host = "smtp.gmail.com";

    props.put("mail.smtp.starttls.enable", "true");

    props.put("mail.smtp.ssl.trust", host);
    props.put("mail.smtp.user", from);
    props.put("mail.smtp.password", pass);
    props.put("mail.smtp.port", "587");
    props.put("mail.smtp.auth", "true");


    Session session = Session.getDefaultInstance(props);
    MimeMessage message = new MimeMessage(session);

    try {


        message.setFrom(new InternetAddress(from));
        InternetAddress[] toAddress = new InternetAddress[to.length];

        // To get the array of addresses
        for( int i = 0; i < to.length; i++ ) {
            toAddress[i] = new InternetAddress(to[i]);
        }

        for( int i = 0; i < toAddress.length; i++) {
            message.addRecipient(Message.RecipientType.TO, toAddress[i]);
        }



        message.setSubject(subject);
        message.setText(body);


        Transport transport = session.getTransport("smtp");


        transport.connect(host, from, pass);
        transport.sendMessage(message, message.getAllRecipients());
        transport.close();

    }
    catch (AddressException ae) {
        ae.printStackTrace();
    }
    catch (MessagingException me) {
        me.printStackTrace();
    }
    }
   } 

NB:-check your internet connection