带有 OpenJDK 11 的 Jakarta Mail：java.util.ServiceConfigurationError：jakarta.mail.Provider：Provider com.sun.mail.imap.IMAPProvider 不是子类型

编程问答 2022-05-25

问题描述

我正在从 java 8 迁移到 openjdk-11。现在邮件（用 smtp 发送电子邮件）不再起作用。该项目在 Win10 上使用 openjdki 11 和 jakarta.mail-2.0.0。后来我加了jakarta.activation-api-2.0.0。

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

    Session session = Session.getInstance(props);
    session.setDebug(debug);

    try {
        // create a message
        MimeMessage message = new MimeMessage(session);
        message.setFrom(new InternetAddress(from));
        message.setRecipients(Message.RecipientType.TO,InternetAddress.parse(to));
        message.setSubject("Jakarta Mail API Test");
        message.setSentDate(new Date());

        MimeBodyPart mbp1 = new MimeBodyPart();
        mbp1.setText("This is a message body.\nHere's line two.");
        MimeBodyPart mbp2 = new MimeBodyPart();
        mbp2.setText("This is the text in the message attachment.","us-ascii");
        Multipart mp = new MimeMultipart();
        mp.addBodyPart(mbp1);
        message.setContent(mp);
        Transport.send(message);
    } catch (MessagingException mex) {
        mex.printstacktrace();
        Exception ex = null;
        if ((ex = mex.getNextException()) != null) {
            ex.printstacktrace();
        }
    }

代码可以编译，但不能运行：

Exception in thread "main" java.util.ServiceConfigurationError: jakarta.mail.Provider: Provider com.sun.mail.imap.IMAPProvider not a subtype
at java.util.ServiceLoader.fail(ServiceLoader.java:239)
at java.util.ServiceLoader.access$300(ServiceLoader.java:185)
at java.util.ServiceLoader$LazyIterator.nextService(ServiceLoader.java:376)
at java.util.ServiceLoader$LazyIterator.next(ServiceLoader.java:404)
at java.util.ServiceLoader$1.next(ServiceLoader.java:480)
at jakarta.mail.Session.loadProviders(Session.java:964)
at jakarta.mail.Session.<init>(Session.java:254)
at jakarta.mail.Session.getInstance(Session.java:281)
at test.transport.main(transport.java:51)
C:\Users\<user>\Documents\Netbeansprojects12.0\AC99_Benutzer\nbproject\build-impl.xml:1370: The following error occurred while executing this line:
C:\Users\<user>\Documents\Netbeansprojects12.0\AC99_Benutzer\nbproject\build-impl.xml:993: Java returned: 1
BUILD Failed (total time: 0 seconds)

解决方法

Per Jakarta Mail home page：Artfact jakarta.mail 是实现，jakarta.mail-api 只能用于编译。仅与 provided 依赖范围一起使用。

使用上面的链接并下载 jakarta.mail.jar。删除 jakarta.mail-api.jar。添加 jakarta.mail.jar

jakarta-mailopenjdk-11