Styjun

Try to send an email using java. Find an example from: https://www.codejava.net/java-ee/javamail/send-e-mail-in-html-format-using-javamail-api.

However, when try to send the email, it looks like the code stuck at Transport.send(msg); and doesn't make any progress anymore. And it also not timed out.

import java.util.Date;
import java.util.Properties;

import javax.mail.Authenticator;
import javax.mail.Message;
import javax.mail.MessagingException;
import javax.mail.PasswordAuthentication;
import javax.mail.Session;
import javax.mail.Transport;
import javax.mail.internet.AddressException;
import javax.mail.internet.InternetAddress;
import javax.mail.internet.MimeMessage;

import lombok.extern.slf4j.Slf4j;

@Slf4j
public class HtmlEmailSender 

 public void sendHtmlEmail(String host, String port,
 final String userName, final String password, String toAddress,
 String subject, String message) throws AddressException,
 MessagingException 

 // sets SMTP server properties
 Properties properties = new Properties();
 properties.put("mail.smtp.host", host);
 properties.put("mail.smtp.port", port);
 properties.put("mail.smtp.auth", "true");
 properties.put("mail.smtp.starttls.enable", "true");

 // creates a new session with an authenticator
 Authenticator auth = new Authenticator() 
 public PasswordAuthentication getPasswordAuthentication() 
 return new PasswordAuthentication(userName, password);
 
 ;

 Session session = Session.getInstance(properties, auth);

 // creates a new e-mail message
 Message msg = new MimeMessage(session);

 msg.setFrom(new InternetAddress(userName));
 InternetAddress[] toAddresses = new InternetAddress(toAddress) ;
 msg.setRecipients(Message.RecipientType.TO, toAddresses);
 msg.setSubject(subject);
 msg.setSentDate(new Date());
 // set plain text message
 msg.setContent(message, "text/html");

 // sends the e-mail
 Transport.send(msg);
 log.info("Success!");

 

 /**
 * Test the send html e-mail method
 *
 */
 public static void main(String[] args) 
 // SMTP server information
 String host = "smtp.gmail.com";
 String port = "587";
 String mailFrom = "fromemail@gmail.com";
 String password = "password";

 // outgoing message information
 String mailTo = "toemail@gmail.com";
 String subject = "Hello my friend";

 // message contains HTML markups
 String message = "<i>Greetings!</i><br>";
 message += "<b>Wish you a nice day!</b><br>";
 message += "<font color=red>Duke</font>";

 HtmlEmailSender mailer = new HtmlEmailSender();

 try 
 mailer.sendHtmlEmail(host, port, mailFrom, password, mailTo,
 subject, message);
 System.out.println("Email sent.");
 catch (Exception ex) 
 System.out.println("Failed to sent email.");
 ex.printStackTrace();
 
 

UPDATE:
I was able to get rid of the initial issue by turning on the IMAP optional for my gmail account. But then I got another exception:

DEBUG: setDebug: JavaMail version 1.6.0
DEBUG: getProvider() returning javax.mail.Provider[TRANSPORT,smtp,com.sun.mail.smtp.SMTPTransport,Oracle]
DEBUG SMTP: need username and password for authentication
DEBUG SMTP: protocolConnect returning false, host=smtp.gmail.com, user='myusername', password=<null>
DEBUG SMTP: useEhlo true, useAuth true
DEBUG SMTP: trying to connect to host "smtp.gmail.com", port 587, isSSL true
Failed to sent email.
com.sun.mail.util.MailConnectException: Couldn't connect to host, port: smtp.gmail.com, 587; timeout -1;
 nested exception is:
 java.net.ConnectException: Operation timed out (Connection timed out)
 at com.sun.mail.smtp.SMTPTransport.openServer(SMTPTransport.java:2194)
 at com.sun.mail.smtp.SMTPTransport.protocolConnect(SMTPTransport.java:726)
 at javax.mail.Service.connect(Service.java:388)
 at javax.mail.Service.connect(Service.java:246)
 at javax.mail.Service.connect(Service.java:195)
 at javax.mail.Transport.send0(Transport.java:254)
 at javax.mail.Transport.send(Transport.java:124)
 at insbot.HtmlEmailSender.sendHtmlEmail(HtmlEmailSender.java:55)
 at insbot.HtmlEmailSender.main(HtmlEmailSender.java:83)
Caused by: java.net.ConnectException: Operation timed out (Connection timed out)
 at java.net.PlainSocketImpl.socketConnect(Native Method)
 at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:350)
 at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:206)
 at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:188)
 at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392)
 at java.net.Socket.connect(Socket.java:589)
 at java.net.Socket.connect(Socket.java:538)
 at com.sun.mail.util.SocketFetcher.createSocket(SocketFetcher.java:352)
 at com.sun.mail.util.SocketFetcher.getSocket(SocketFetcher.java:238)
 at com.sun.mail.smtp.SMTPTransport.openServer(SMTPTransport.java:2160)
 ... 8 more