Apache Commons电子邮件和重用SMTP连接

Question

目前我使用Commons Email发送电子邮件,但我找不到在发送的电子邮件之间共享smtp连接的方法.我有以下代码:

    Email email = new SimpleEmail();
    email.setFrom("example@example.com");
    email.addTo("example@example.com");
    email.setSubject("Hello Example");
    email.setMsg("Hello Example");
    email.setSmtpPort(25);
    email.setHostName("localhost");
    email.send();

这是非常易读的,但是当我执行大量消息时速度很慢,我认为这是重新连接每条消息的开销.因此,我使用以下代码对其进行了分析,并发现使用重新使用Transport会使事情快三倍.

    Properties props = new Properties();
    props.setProperty("mail.transport.protocol", "smtp");
    Session mailSession = Session.getDefaultInstance(props, null);
    Transport transport = mailSession.getTransport("smtp");
    transport.connect("localhost", 25, null, null);

    MimeMessage message = new MimeMessage(mailSession);
    message.setFrom(new InternetAddress("example@example.com"));
    message.addRecipient(Message.RecipientType.TO, new InternetAddress("example@example.com"));
    message.setSubject("Hello Example");
    message.setContent("Hello Example", "text/html; charset=ISO-8859-1");

    transport.sendMessage(message, message.getAllRecipients());

所以我想知道是否有办法让Commons Email重用多个电子邮件发送的SMTP连接？我更喜欢Commons Email API,但性能有点痛苦.

谢谢,赎金

Answer 1

在深入研究公共资源本身后，我想出了以下解决方案。这应该可行，但可能有更好的解决方案我不知道

    Properties props = new Properties();
    props.setProperty("mail.transport.protocol", "smtp");
    Session mailSession = Session.getDefaultInstance(props, null);
    Transport transport = mailSession.getTransport("smtp");
    transport.connect("localhost", 25, null, null);

    Email email = new SimpleEmail();
    email.setFrom("example@example.com");
    email.addTo("example@example.com");
    email.setSubject("Hello Example");
    email.setMsg("Hello Example");
    email.setHostName("localhost"); // buildMimeMessage call below freaks out without this

    // dug into the internals of commons email
    // basically send() is buildMimeMessage() + Transport.send(message)
    // so rather than using Transport, reuse the one that I already have
    email.buildMimeMessage();
    Message m = email.getMimeMessage();
    transport.sendMessage(m, m.getAllRecipients());