JavaMail API Part 1 - Sending simple text email

There are many applications where system has to send an email to the user.

• Notification
• Validation
• Reporting
• Alarming etc

Sending email though look simple but it has many things to be considered like 

• Whether email is a rich text or simple text
• Whether email has attachment
• Email using authentication
• Emailing using secured protocols and mechanisms

Let's first take a simple case of sending a simple text email. We can write a simple standalone java application to send email. 

Prerequisites

We will need  JavaMail API and Java Activation Framework (JAF). You can download latest version from Oracle website.

• JavaMail API
• JAF

Download and unzip these files, in the newly created top level directories you will find a number of jar files for both the applications. You need to add mail.jar and activation.jar files in your CLASSPATH.

We will also need mail server to send an email. There are many open source mail server we can use or we can use inbuilt mail server from operating system. Let's assume that mail server is running on localhost.

Sending Text Email

Following is the code.

// File Name SendMail.java


import java.util.*;

import javax.mail.*;

import javax.mail.internet.*;

import javax.activation.*;



public class SendMail

{

   public static void main(String [] args)

   {
    

      // Recipient's email ID needs to be mentioned.

      String to = "abcd@gmail.com";

      // Sender's email ID needs to be mentioned

      String from = "web@gmail.com";

      // Assuming you are sending email from localhost

      String host = "localhost";

      // Get system properties

      Properties properties = System.getProperties();

      // Setup mail server

      properties.setProperty("mail.smtp.host", host);

      // Get the default Session object.

      Session session = Session.getDefaultInstance(properties);

      try{

         // Create a default MimeMessage object.

         MimeMessage message = new MimeMessage(session);

         // Set From: header field of the header.

         message.setFrom(new InternetAddress(from));

         // Set To: header field of the header.

         message.addRecipient(Message.RecipientType.TO, new InternetAddress(to));

         // Set Subject: header field

         message.setSubject("This is the Subject Line!");

         // Now set the actual message

         message.setText("This is actual message");

         // Send message

         Transport.send(message);

         System.out.println("Sent message successfully....");

      }catch (MessagingException mex) {

         mex.printStackTrace();

      }

   }

}

Compile and run this program to send a simple email:

$ java SendMail

Sent message successfully....

Sending Email to multiple recipient

If you want to send an email to multiple recipients then following methods would be used to specify multiple email IDs:

void addRecipients(Message.RecipientType type, Address [] addresses) MessagingException

Here is the description of the parameters:

• type: This would be set to TO, CC or BCC. Here CC represents Carbon Copy and BCC represents Black Carbon Copy. Example Message.RecipientType.TO
• addresses: This is the array of email ID. You would need to use InternetAddress() method while specifying email IDs