check wether an EmailId is in existence or not in java.

When Am sending a message using Java Mail API its not throwing any exception for an invalid email.

Thanks&Regards,
Sindhu

The below mentioned is my code which doesn't have a functionality of checking recipient email is valid or not.Can u please suggest me how to add that functionality.

String to = "abc@gmail.com";

// Sender's email ID needs to be mentioned
String from = "validemail@gmail.com ";
final String username = "validemail@gmail.com";//change accordingly
final String password = "********";//change accordingly

// Assuming you are sending email through relay.jangosmtp.net
String host = "smtp.gmail.com";

Properties props = new Properties();

props.put("mail.smtp.auth", "true");
props.put("mail.smtp.starttls.enable", "true");
props.setProperty("mail.smtp.protocol", "smtps");
props.setProperty("mail.smtp.ssl.enable", "true");
props.put("mail.smtp.host", host);
props.put("mail.smtp.port", "587");
// props.setProperty("mail.smtp.user", username);

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

try {

// Create a default MimeMessage object.
Message message = new MimeMessage(session);

// Set From: header field of the header.
message.setFrom(new InternetAddress(from));

// Set To: header field of the header.
message.setRecipients(Message.RecipientType.TO,
InternetAddress.parse(to));

// Set Subject: header field
message.setSubject("Testing Subject");

// This mail has 2 part, the BODY and the embedded image
MimeMultipart multipart = new MimeMultipart("related");

// first part (the html)
BodyPart messageBodyPart = new MimeBodyPart();

String htmlText = null;
if("userRegistered".equals(request))
{
System.out.println("if loop");
htmlText = getHtmlDataforReg_User(emailId,userName,userPassword);
}
else
{
System.out.println("else loop");
htmlText = getHtmlData(userName,userPassword);
}
messageBodyPart.setContent(htmlText, "text/html");
// add it
multipart.addBodyPart(messageBodyPart);

// put everything together
message.setContent(multipart);
// Send message
Transport.send(message);

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

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