java.lang.RuntimeException：javax.mail.MessagingException：无法连接到SMTP主机：smtp.gmail.com，端口：465

Question

大家好！

我一直在尝试使用JavaMail API

// Recipient's email ID needs to be mentioned.
          String to = "toaddrs@gmail.com";//change accordingly

          // Sender's email ID needs to be mentioned
          String from = "fromaddrs@gmail.com";//change accordingly
          final String email = "emailaddrs@gmail.com";//change accordingly
          final String password = "xxxxxxxxx";//change accordingly

          // Assuming you are sending email through relay.jangosmtp.net
          String host = "smtp.gmail.com";

          Properties props = new Properties();
          props.put("mail.smtp.auth", "true");
          props.put("mail.smtp.starttls.enable", "true");
          props.put("mail.smtp.host", host);
          props.put("mail.smtp.port", "465");

          // Get the Session object.
          Session session = Session.getInstance(props,
          new javax.mail.Authenticator() {
             protected PasswordAuthentication getPasswordAuthentication() {
                return new PasswordAuthentication(email, password);
             }
          });

          try {
             // Create a default MimeMessage object.
             Message message = new MimeMessage(session);

             // Set From: header field of the header.
             message.setFrom(new InternetAddress(from));

             // Set To: header field of the header.
             message.setRecipients(Message.RecipientType.TO,
             InternetAddress.parse(to));

             // Set Subject: header field
             message.setSubject("Testing Subject");

             // Now set the actual message
             message.setText("Hello, this is sample for to check send "
                + "email using JavaMailAPI ");

             // Send message
             Transport.send(message);

             System.out.println("Sent message successfully....");

          } catch (MessagingException e) {
                throw new RuntimeException(e);
          }

该程序似乎没有错误，执行后我得到：

java.lang.RuntimeException：javax.mail.MessagingException：无法连接到SMTP主机：smtp.gmail.com，端口：465； 嵌套的异常是：java.net.ConnectException：连接超时：connect

有人可以帮我吗？？？ <<->是的，我已经配置了对不太安全的应用程序的GMail访问权限。...>>

提前Thnks！

Answer 1

使用TLS通过Gmail SMTP服务器发送邮件时，应使用端口587

Properties props = new Properties();
props.put("mail.smtp.auth", "true");
props.put("mail.smtp.starttls.enable", "true");
props.put("mail.smtp.host", host);
props.put("mail.smtp.port", "587");

端口465用于使用SSL发送电子邮件，应如下所示

Properties props = new Properties();
props.put("mail.smtp.host", host);
props.put("mail.smtp.socketFactory.port", "465");
props.put("mail.smtp.socketFactory.class","javax.net.ssl.SSLSocketFactory");
props.put("mail.smtp.auth", "true");
props.put("mail.smtp.port", "465");

Answer 2

您的防火墙，代理或防病毒程序可能阻止了直接连接。

JavaMail FAQ 提供了通过代理连接的技巧和调试技巧，以帮助确定为什么无法连接 。