JavaMail API 错误 (javax.mail.NoSuchProviderException : invalid provider)

Question

我正在尝试使用 JavaMail API 创建一个程序，但是，我不断收到以下错误消息。

javax.mail.NoSuchProviderException: invalid provider
at javax.mail.Session.getTransport(Session.java:738)
at javax.mail.Session.getTransport(Session.java:682)
at javax.mail.Session.getTransport(Session.java:662)
at EmailAutoResponder2.main(EmailAutoResponder2.java:56)

我无法通过在线阅读来解决这个问题，因为他们所有的解决方案仍然给了我同样的信息。

这是Java代码:

import java.util.*;
import javax.mail.*;
import javax.mail.internet.*;

public class EmailAutoResponder2 {

public static void main(String[] args) {

    String to = "username@videotron.ca";
    String from = "username@videotron.ca";

    Properties properties = System.getProperties();

    properties.setProperty("mail.store.protocol", "imaps");

    Session session1 = Session.getInstance(properties);

    //If email received by specific user, send particular response.
    Properties props = new Properties();

    props.put("mail.imap.auth", "true");
    props.put("mail.imap.starttls.enable", "true");
    props.put("mail.imap.host", "imap.videotron.ca");
    props.put("mail.imap.port", "143");

    Session session2 = Session.getInstance(props, new Authenticator() {

                protected PasswordAuthentication getPasswordAuthentication() {
                        return new PasswordAuthentication("username@videotron.ca", "password");
            }
        });

    try {
        Store store = session2.getStore("imap");
        store.connect("imap.videotron.ca", "username@videotron.ca", "password");
        Folder fldr = store.getFolder("Inbox");
        fldr.open(Folder.READ_ONLY);
        Message msgs[] = fldr.getMessages(); 
            for(int i = 0; i < msgs.length; i++){
                System.out.println(InternetAddress.toString(msgs[i].getFrom()));

            if (InternetAddress.toString(msgs[i].getFrom()).startsWith("Name")){

                MimeMessage message = new MimeMessage(session1);

                message.setFrom(new InternetAddress(from));
                message.addRecipient(Message.RecipientType.TO, new InternetAddress(to));
                message.setSubject("Subject");
                message.setText("Message");

                String protocol = "imap";
                props.put("mail." + protocol + ".auth", "true");

                Transport t = session2.getTransport("imap");
                try {
                    t.connect("username@videotron.ca", "password");
                    t.sendMessage(message, message.getAllRecipients());
                }
                finally {
                    t.close();
                }

            }
            }

    }

    catch(MessagingException mex){
        mex.printStackTrace();
    }

    catch(Exception exc) {

    }

    }

    }

谢谢!

Answer 1

您正在连接到本地主机来发送消息。您的本地计算机上有运行邮件服务器吗？可能不会。您需要设置 mail.smtp.host 属性。您可能还需要提供邮件服务器的用户名和密码；请参阅JavaMail FAQ .