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java_sending_email

To send an e-mail using your Java Application is simple enough but to start with you should have JavaMail API and Java Activation Framework (JAF)installed on your machine.
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.

Send a Simple E-mail

Here is an example to send a simple e-mail from your machine. It is assumed that your localhost is connected to the Internet and capable enough to send an e-mail.

Example

// File Name SendEmail.java

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

public class SendEmail {

   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 e-mail −

Output

$ java SendEmail
Sent message successfully....
If you want to send an e-mail to multiple recipients then the following methods would be used to specify multiple e-mail IDs −
void addRecipients(Message.RecipientType type, Address[] addresses)
   throws 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 an array of e-mail ID. You would need to use InternetAddress() method while specifying email IDs.

Send an HTML E-mail

Here is an example to send an HTML e-mail from your machine. Here it is assumed that your localhost is connected to the Internet and capable enough to send an e-mail.
This example is very similar to the previous one, except here we are using setContent() method to set content whose second argument is "text/html" to specify that the HTML content is included in the message.
Using this example, you can send as big as HTML content you like.

Example

// File Name SendHTMLEmail.java

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

public class SendHTMLEmail {

   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!");

         // Send the actual HTML message, as big as you like
         message.setContent("<h1>This is actual message</h1>", "text/html");

         // Send message
         Transport.send(message);
         System.out.println("Sent message successfully....");
      } catch (MessagingException mex) {
         mex.printStackTrace();
      }
   }
}
Compile and run this program to send an HTML e-mail −

Output

$ java SendHTMLEmail
Sent message successfully....

Send Attachment in E-mail

Here is an example to send an e-mail with attachment from your machine. Here it is assumed that your localhost is connected to the internet and capable enough to send an e-mail.

Example

// File Name SendFileEmail.java

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

public class SendFileEmail {

   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!");

         // Create the message part 
         BodyPart messageBodyPart = new MimeBodyPart();

         // Fill the message
         messageBodyPart.setText("This is message body");
         
         // Create a multipar message
         Multipart multipart = new MimeMultipart();

         // Set text message part
         multipart.addBodyPart(messageBodyPart);

         // Part two is attachment
         messageBodyPart = new MimeBodyPart();
         String filename = "file.txt";
         DataSource source = new FileDataSource(filename);
         messageBodyPart.setDataHandler(new DataHandler(source));
         messageBodyPart.setFileName(filename);
         multipart.addBodyPart(messageBodyPart);

         // Send the complete message parts
         message.setContent(multipart );

         // Send message
         Transport.send(message);
         System.out.println("Sent message successfully....");
      } catch (MessagingException mex) {
         mex.printStackTrace();
      }
   }
}
Compile and run this program to send an HTML e-mail −

Output

$ java SendFileEmail
Sent message successfully....

User Authentication Part

If it is required to provide user ID and Password to the e-mail server for authentication purpose, then you can set these properties as follows −
props.setProperty("mail.user", "myuser");
props.setProperty("mail.password", "mypwd");
Rest of the e-mail sending mechanism would remain as explained above.

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