MailService.java

@Service
public class MailService implements MailServiceI {

    @Value("${smtp.host}")
    private String host;

    @Value("${smtp.auth}")
    private String auth;

    @Value("${smtp.port}")
    private String port;

    @Value("${smtp.username}")
    private String username;

    @Value("${smtp.email-from}")
    private String fromMail;

    @Value("${smtp.email-from-name}")
    private String fromName;

    @Value("${smtp.password}")
    private String password;

    @Override
    public void sendNewMail(String email, String mailMessage, String subject) throws MailNotSentException {

      Properties props = new Properties();
      props.put("mail.smtp.auth", auth);
      props.put("mail.smtp.host", host);
      props.put("mail.smtp.port", port);
      Session session = Session.getInstance(props);
      
      Message message = new MimeMessage(session);
      message.setFrom(new InternetAddress(fromMail, fromName));
      message.setRecipients(Message.RecipientType.TO, InternetAddress.parse(email));
      message.setSubject(subject);
      message.setContent(mailMessage, "text/html; charset=utf-8");

      Transport.send(message, username, password);
      
    }

}

related to medium article https://medium.com/nerd-for-tech/using-jboss-credential-store-in-a-spring-application-4bacfd2d9e96