javax.mail.NoSuchProviderException : smtp

Question

以下是我发送电子邮件的代码:

    Properties props = new Properties();
    props.put("mail.smtp.host", host);
    props.put("mail.debug", "false");

    final Session session = Session.getInstance(props);
    final Message msg = new MimeMessage(session);
    msg.setFrom(new InternetAddress(from));
    msg.setRecipients(Message.RecipientType.TO, toAddress);
    msg.setSubject(subject);
    msg.setSentDate(new Date());
    Multipart multipart = new MimeMultipart("related");
    BodyPart mbp1 = new MimeBodyPart();
    mbp1.setContent(body, "text/html");         
    multipart.addBodyPart(mbp1);
    Transport.send(msg);

错误堆栈跟踪:

javax.mail.NoSuchProviderException: smtp
    at javax.mail.Session.getService(Session.java:764)
    at javax.mail.Session.getTransport(Session.java:689)
    at javax.mail.Session.getTransport(Session.java:632)
    at javax.mail.Session.getTransport(Session.java:612)
    at javax.mail.Session.getTransport(Session.java:667)
    at javax.mail.Transport.send0(Transport.java:154)
    at javax.mail.Transport.send(Transport.java:80)

笔记:

1. Same code works if executed as a desktop application. But throws above exception when deployed on tomcat.
2. Latest mail.jar and smtp.jar are added to library.
3. SMTP host address is also correct.

如果有人可以给我指点，那将是有帮助的。

Answer 1

我也遇到了类似的情况，但最终可以解决它。就我而言，问题是 proguard_rules.txt我需要添加的文件:

-keep class javax.mail.** {*;}
-keep class javax.activation.** {*;}
-keep class com.sun.mail.dsn.** {*;}
-keep class com.sun.mail.handlers.** {*;}
-keep class com.sun.mail.smtp.** {*;}
-keep class com.sun.mail.util.** {*;}