Getting Started With Creating A Java Email Client
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.
You can download the latest version of JavaMail (Version 1.5.4) from the JavaMail API site. The site also hosts the API documentation.
You can download latest version of JAF (Version 1.1.1) from here.
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. Here it is assumed that your localhost is connected to the internet and capable enough to send an email.
// 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:
java SendEmail
Sent message successfully....
If you want to send an e-mail to multiple recipients then 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 the array of email 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 email from your machine. Here it is assumed that your localhost is connected to the internet and capable enough to send an email.
This example is very similar to 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.
// 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:
$ java SendHTMLEmail
Sent message successfully....
Send Attachment in E-mail:
Here is an example to send an email with attachment from your machine. Here it is assumed that your localhost is connected to the internet and capable enough to send an email.
// 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:
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.
References
First published: 16th August 2018