E-Mailing Through Java Mail
* You use the JavaMail API where as JavaMail implementation providers implement the JavaMail API to give you a JavaMail client (Java JAR file). Sun gives you mail.jar which has Sun's SMTP, POP3 and IMAP client implementations along with the JavaMail API. This is sufficient to send and receive e-mail but not to read or post to newgroups which use NNTP.
Sample Code to Send E-Mail
* To compile and run, you must have mail.jar (from the JavaMail download) and activation.jar (from the JavaBeans Activation Framework download) in Java classpath.
* You need to replace email addresses and mail server with your values where noted. Username and password is generally not needed to send e-mail although your ISP may still require it to prevent spam from going through its systems.
import javax.mail.*;
import javax.mail.internet.*;
import javax.activation.*;
// Send a simple, single part, text/plain e-mail
public class TestEmail {
public static void main(String[] args) {
// SUBSTITUTE YOUR EMAIL ADDRESSES HERE!!!
String to = "vipan@vipan.com";
String from = "vipan@vipan.com";
// SUBSTITUTE YOUR ISP'S MAIL SERVER HERE!!!
String host = "smtp.yourisp.net";
// Create properties, get Session
Properties props = new Properties();
// If using static Transport.send(),
// need to specify which host to send it to
props.put("mail.smtp.host", host);
// To see what is going on behind the scene
props.put("mail.debug", "true");
Session session = Session.getInstance(props);
try {
// Instantiatee a message
Message msg = new MimeMessage(session);
//Set message attributes
msg.setFrom(new InternetAddress(from));
InternetAddress[] address = {new InternetAddress(to)};
msg.setRecipients(Message.RecipientType.TO, address);
msg.setSubject("Test E-Mail through Java");
msg.setSentDate(new Date());
// Set message content
msg.setText("This is a test of sending a " +
"plain text e-mail through Java.\n" +
"Here is line 2.");
//Send the message
Transport.send(msg);
}
catch (MessagingException mex) {
// Prints all nested (chained) exceptions as well
mex.printStackTrace();
}
}
}//End of class
Sample Code to Send Multipart E-Mail, HTML E-Mail and File Attachments
* To compile and run, you must have mail.jar (from the JavaMail download) and activation.jar (from the JavaBeans Activation Framework download) in Java classpath.
* You need to replace email addresses and mail server with your values where noted.
* This sample code has debugging turned on ("mail.debug") to see what is going on behind the scenes in JavaMail code.
import java.util.*;
import java.io.*;
import javax.mail.*;
import javax.mail.internet.*;
import javax.activation.*;
public class SendMailUsage {
public static void main(String[] args) {
// SUBSTITUTE YOUR EMAIL ADDRESSES HERE!!!
String to = "you@yourisp.net";
String from = "you@yourisp.net";
// SUBSTITUTE YOUR ISP'S MAIL SERVER HERE!!!
String host = "smtpserver.yourisp.net";
// Create properties for the Session
Properties props = new Properties();
// If using static Transport.send(),
// need to specify the mail server here
props.put("mail.smtp.host", host);
// To see what is going on behind the scene
props.put("mail.debug", "true");
// Get a session
Session session = Session.getInstance(props);
try {
// Get a Transport object to send e-mail
Transport bus = session.getTransport("smtp");
// Connect only once here
// Transport.send() disconnects after each send
// Usually, no username and password is required for SMTP
bus.connect();
//bus.connect("smtpserver.yourisp.net", "username", "password");
// Instantiate a message
Message msg = new MimeMessage(session);
// Set message attributes
msg.setFrom(new InternetAddress(from));
InternetAddress[] address = {new InternetAddress(to)};
msg.setRecipients(Message.RecipientType.TO, address);
// Parse a comma-separated list of email addresses. Be strict.
msg.setRecipients(Message.RecipientType.CC,
InternetAddress.parse(to, true));
// Parse comma/space-separated list. Cut some slack.
msg.setRecipients(Message.RecipientType.BCC,
InternetAddress.parse(to, false));
msg.setSubject("Test E-Mail through Java");
msg.setSentDate(new Date());
// Set message content and send
setTextContent(msg);
msg.saveChanges();
bus.sendMessage(msg, address);
setMultipartContent(msg);
msg.saveChanges();
bus.sendMessage(msg, address);
setFileAsAttachment(msg, "C:/WINDOWS/CLOUD.GIF");
msg.saveChanges();
bus.sendMessage(msg, address);
setHTMLContent(msg);
msg.saveChanges();
bus.sendMessage(msg, address);
bus.close();
}
catch (MessagingException mex) {
// Prints all nested (chained) exceptions as well
mex.printStackTrace();
// How to access nested exceptions
while (mex.getNextException() != null) {
// Get next exception in chain
Exception ex = mex.getNextException();
ex.printStackTrace();
if (!(ex instanceof MessagingException)) break;
else mex = (MessagingException)ex;
}
}
}
// A simple, single-part text/plain e-mail.
public static void setTextContent(Message msg) throws MessagingException {
// Set message content
String mytxt = "This is a test of sending a " +
"plain text e-mail through Java.\n" +
"Here is line 2.";
msg.setText(mytxt);
// Alternate form
msg.setContent(mytxt, "text/plain");
}
// A simple multipart/mixed e-mail. Both body parts are text/plain.
public static void setMultipartContent(Message msg) throws MessagingException {
// Create and fill first part
MimeBodyPart p1 = new MimeBodyPart();
p1.setText("This is part one of a test multipart e-mail.");
// Create and fill second part
MimeBodyPart p2 = new MimeBodyPart();
// Here is how to set a charset on textual content
p2.setText("This is the second part", "us-ascii");
// Create the Multipart. Add BodyParts to it.
Multipart mp = new MimeMultipart();
mp.addBodyPart(p1);
mp.addBodyPart(p2);
// Set Multipart as the message's content
msg.setContent(mp);
}
// Set a file as an attachment. Uses JAF FileDataSource.
public static void setFileAsAttachment(Message msg, String filename)
throws MessagingException {
// Create and fill first part
MimeBodyPart p1 = new MimeBodyPart();
p1.setText("This is part one of a test multipart e-mail." +
"The second part is file as an attachment");
// Create second part
MimeBodyPart p2 = new MimeBodyPart();
// Put a file in the second part
FileDataSource fds = new FileDataSource(filename);
p2.setDataHandler(new DataHandler(fds));
p2.setFileName(fds.getName());
// Create the Multipart. Add BodyParts to it.
Multipart mp = new MimeMultipart();
mp.addBodyPart(p1);
mp.addBodyPart(p2);
// Set Multipart as the message's content
msg.setContent(mp);
}
// Set a single part html content.
// Sending data of any type is similar.
public static void setHTMLContent(Message msg) throws MessagingException {
String html = "
" +
msg.getSubject() +
"
This is a test of sending an HTML e-mail" +
" through Java.";
// HTMLDataSource is an inner class
msg.setDataHandler(new DataHandler(new HTMLDataSource(html)));
}
/*
* Inner class to act as a JAF datasource to send HTML e-mail content
*/
static class HTMLDataSource implements DataSource {
private String html;
public HTMLDataSource(String htmlString) {
html = htmlString;
}
// Return html string in an InputStream.
// A new stream must be returned each time.
public InputStream getInputStream() throws IOException {
if (html == null) throw new IOException("Null HTML");
return new ByteArrayInputStream(html.getBytes());
}
public OutputStream getOutputStream() throws IOException {
throw new IOException("This DataHandler cannot write HTML");
}
public String getContentType() {
return "text/html";
}
public String getName() {
return "JAF text/html dataSource to send e-mail only";
}
}
} //End of class
