java - 如何解决 Windows 8 中的 java 7 FTP 传输问题

Question

我使用的是 Windows 8 x86 和 jdk_7。下面的代码编译得很好，没有错误。当我运行时，它给了我这个异常:

javax.mail.MessagingException: Could not connect to SMTP host: localhost, port: 25;
   nested exception is:
java.net.SocketException: Permission denied: connect

现在作为解决方法，我尝试添加此行:

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

这并没有解决问题，经过几个小时的互联网研究，我注意到问题出在 jdk_7 和防火墙问题上。我什至尝试过这个命令

netsh advfirewall set global StatefulFTP disable

这也不能解决问题。

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

public class SendFileEmail
{
  public static void main(String [] args)
  {
     System.setProperty("java.net.preferIPv4Stack", "true");
  // Recipient's email ID needs to be mentioned.
     String to = "tmadile@gmail.com";

  // Sender's email ID needs to be mentioned
     String from = "hareitse@gmail.com";

  // Assuming you are sending email from localhost
     String host = "localhost";

  // Get system properties
     Properties properties = System.getProperties();

  // Setup mail server
     properties.setProperty("mail.smtp.host", host);

  // Get the default Session object.
     Session session = Session.getDefaultInstance(properties);

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

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

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

     // Set Subject: header field
        message.setSubject("This is the Subject Line!");

     // Create the message part 
        BodyPart messageBodyPart = new MimeBodyPart();

     // Fill the message
        messageBodyPart.setText("This is message body");

     // Create a multipar message
        Multipart multipart = new MimeMultipart();

     // Set text message part
        multipart.addBodyPart(messageBodyPart);

     // Part two is attachment
        messageBodyPart = new MimeBodyPart();
        String filename = "shh.jpg";
        DataSource source = new FileDataSource(filename);
        messageBodyPart.setDataHandler(new DataHandler(source));
        messageBodyPart.setFileName(filename);
        multipart.addBodyPart(messageBodyPart);

     // Send the complete message parts
        message.setContent(multipart );

     // Send message
        Transport.send(message);
        System.out.println("Sent message successfully....");
     }
        catch (MessagingException mex) {
           mex.printStackTrace();
        }
  }
}

Answer 1

// Assuming you are sending email from localhost
String host = "localhost";
// Setup mail server
properties.setProperty("mail.smtp.host", host);

我阅读你的代码和你的错误的方式看起来更像是你试图从本地主机作为主机发送，实际上你正在尝试发送到本地主机的邮件服务器的端口 25。如果你没有任何在 localhost 上运行的 SMTP 服务器，您都会收到上述错误。您提供的代码不会为您启动任何 SMTP 服务器。您可能应该将 host = "localhost"替换为您的 smtp 主机(以及可能的其他设置，具体取决于您的 smtp 提供商的需求)。