无法使用Javax.mail发送邮件

Question

I'm trying to send an email on Windows 8.1 with java 1.8 using javax.mail API but I keep getting an error.

Here is the method I wrote:

public void sendAlertMail(String from, String to, String header, String msgBody){
        Properties props = new Properties();
        props.put("mail.transport.protocol", "smtp");
        props.put("mail.smtp.host", smptHost);
        props.put("mail.smtp.port", smptPort);
        props.put("mail.smtp.starttls","true");
        Session mailSession;
        if (authenticate) {
            props.put("mail.smtp.auth", "true");

            Authenticator auth = new SMTPAuthenticator();
            mailSession = Session.getInstance(props, auth);
        }
        else{
            mailSession = Session.getInstance(props);
        }
        // uncomment for debugging infos to stdout
        // mailSession.setDebug(true);
        Transport transport = null;
        try {
            transport = mailSession.getTransport();
        } catch (NoSuchProviderException e) {
            e.printStackTrace();
        }

        MimeMessage message = new MimeMessage(mailSession);
        try {
            message.addHeaderLine(header);
            message.setContent(msgBody, "text/plain");
            message.setFrom(new InternetAddress(from));
            message.addRecipient(Message.RecipientType.TO,
                    new InternetAddress(to));
        } catch (MessagingException e) {
        }
        try {
            transport.connect();
            transport.sendMessage(message,
                    message.getRecipients(Message.RecipientType.TO));
            transport.close();
        } catch (MessagingException e) {
            e.printStackTrace();
        }
    }

And the error I receive is:

com.sun.mail.util.MailConnectException: Couldn't connect to host, port: smtp.gmail.com, 587; timeout -1;
  nested exception is:
    java.net.SocketException: Permission denied: connect
    at com.sun.mail.smtp.SMTPTransport.openServer(SMTPTransport.java:2100)
    at com.sun.mail.smtp.SMTPTransport.protocolConnect(SMTPTransport.java:699)
    at javax.mail.Service.connect(Service.java:388)
    at javax.mail.Service.connect(Service.java:246)
    at javax.mail.Service.connect(Service.java:195)
    at tapperSolution.mail.MailSender.sendAlertMail(MailSender.java:64)
    at tapperSolution.mail.MailSender.sendAlertMail(MailSender.java:74)
    at tapperSolution.mail.MailSender.main(MailSender.java:88)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:497)
    at com.intellij.rt.execution.application.AppMain.main(AppMain.java:140)
Caused by: java.net.SocketException: Permission denied: connect\at java.net.DualStackPlainSocketImpl.connect0(Native Method)
at java.net.DualStackPlainSocketImpl.socketConnect(DualStackPlainSocketImpl.java:79)
at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:350)
at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:206)
at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:188)
at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:172)
at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392)
at java.net.Socket.connect(Socket.java:589)
at java.net.Socket.connect(Socket.java:538)
at com.sun.mail.util.SocketFetcher.createSocket(SocketFetcher.java:331)
at com.sun.mail.util.SocketFetcher.getSocket(SocketFetcher.java:238)
at com.sun.mail.smtp.SMTPTransport.openServer(SMTPTransport.java:2066)
... 12 more

I turned off my firewall and anti virus and I tried to set the VM option in my code using:

System.setProperty("java.net.preferIPv4Stack", "true");

Also tried to set it in the run command with:

-Djava.net.preferIPv4stack=true

I was able to send mail using Python, but I want to do it using Java.

Tried to capture traffic using Wireshark, but there is no even a TCP handshake with the server.

Any other ideas?

Thanks

Answer 1

It looks like your SMTP server may be rejecting your connection, perhaps due to authentication issues. To test this, try a manual SMTP session from the same machine, and see what the result is.