Question

我正在编写一个发送确认电子邮件的servlet。

通常情况下，它工作正常，但是如果我快速调用它几次（延迟时间<1秒）它会因挂在Transport.send上而开始失败，或者它会抛出错误“无法连接到SMTP主机：mail。[domain] .org，port：25“并且堆栈跟踪解释了它超时。我最初认为这是一个线程问题，但即使我只是在一个线程上循环调用它们之间有一个短暂的延迟，它也会发生。我正在使用已建立的ISP作为邮件服务器，因此它似乎应该能够处理超过1个请求/秒。有谁知道如何解决这个问题？

private void sendConfirmationEmail (String email, String invitationID){

    log.info("sendConfirmationEmail called");

    String body = "Sample email sent to " + email;

    initSession();

    try {

        MimeMessage message = new MimeMessage(mySession);
        message.setFrom(new InternetAddress(FROM, "Test account"));

        message.addRecipient(Message.RecipientType.TO, new InternetAddress(email));
        message.setSubject(SUBJECT);
        message.setText(body);

        log.info("about to send over transport for " + email);
        Transport.send(message);
        log.info("Email sent");

    }
    catch (MessagingException e) {
        log.log(Level.SEVERE, "Could not send confirmation email: " + e.getMessage());
    }
    catch (java.io.UnsupportedEncodingException e){
        log.log(Level.WARNING, "Unsupported Encoding");
    }
}

我正在使用以下代码将会话初始化为静态变量：

public static void initSession () {
    if (mySession == null){

        Properties props = new Properties();
        props.put("mail.smtp.host", HOST);
        props.put("mail.smtp.auth", "true");

        mySession = Session.getDefaultInstance(props, new javax.mail.Authenticator(){
                protected PasswordAuthentication getPasswordAuthentication() {
                    return new PasswordAuthentication(SMTP_USERNAME, SMTP_PASSWORD);
                }
            });

    }
}

Answer 1

尝试在初始化期间设置属性connectiontimeout和timeout

public static void initSession () {
  if (mySession == null){

    Properties props = new Properties();
    props.put("mail.smtp.host", HOST);
    props.put("mail.smtp.auth", "true");
    props.put("mail.smtp.connectiontimeout", 1200);
    props.put("mail.smtp.timeout", 1000);

    mySession = Session.getDefaultInstance(props, new javax.mail.Authenticator(){
            protected PasswordAuthentication getPasswordAuthentication() {
                return new PasswordAuthentication(SMTP_USERNAME, SMTP_PASSWORD);
            }
        });

}

}

当调用太频繁时，Java.mail超时

1 个答案: