import java.util.Properties; import javax.activation.DataSource; import javax.mail.Authenticator; import javax.mail.Message; import javax.mail.MessagingException; import javax.mail.PasswordAuthentication; import javax.mail.Session; import org.apache.logging.log4j.util.PropertiesUtil; class JavaMail { public static void main(String[] args) { // BAD: Don't have server certificate check { final Properties properties = PropertiesUtil.getSystemProperties(); properties.put("mail.transport.protocol", "protocol"); properties.put("mail.smtp.host", "hostname"); properties.put("mail.smtp.socketFactory.class", "classname"); final Authenticator authenticator = buildAuthenticator("username", "password"); if (null != authenticator) { properties.put("mail.smtp.auth", "true"); } final Session session = Session.getInstance(properties, authenticator); } // GOOD: Have server certificate check { final Properties properties = PropertiesUtil.getSystemProperties(); properties.put("mail.transport.protocol", "protocol"); properties.put("mail.smtp.host", "hostname"); properties.put("mail.smtp.socketFactory.class", "classname"); final Authenticator authenticator = buildAuthenticator("username", "password"); if (null != authenticator) { properties.put("mail.smtp.auth", "true"); properties.put("mail.smtp.ssl.checkserveridentity", "true"); } final Session session = Session.getInstance(properties, authenticator); } } }