javamail有一些新问题，高手们解决了一定会给分你们的。

Question

你也可以看看后台打印了什么信息，其实后台的信息也很重要的21cn发邮件需要smtp认证，你需要写一个认证类，有没有啊？

Answer 1

http://expert.csdn.net/Expert/topic/874/874715.xml?temp=.4623377

Answer 2

我的源代码为下面两大段，希望各位高手给于意见和解决谢谢。
<%@ page language="java" import="java.util.*,javax.mail.*,javax.mail.internet.*,SmtpAuth,javax.activation.*"%>
<%try{
            String host="smtp.21cn.com";
            String from="****@21cn.com";
            String to="****@21cn.com";
            String username="****";
            String password="****";
            String body="hello ,this is only a test!";            // Get system properties
            // Properties props = System.getProperties(); 很多例子中是这样的，其实下面这句更好，可以用在applet中
            Properties props = new Properties();
            // Setup mail server
            props.put("mail.transport.protocol", "smtp");
            props.put("mail.smtp.host", host);
            props.put("mail.smtp.port","25");
            //props.put("mail.transport.protocol", "true"); //这样才能通过验证
            System.out.println("error is cause?\n");
           props.put("mail.smtp.auth", "true");
            // Get session
           // Session sessionDLT = Session.getDefaultInstance(props);
//           javax.mail.PasswordAuthentication sa=new javax.mail.PasswordAuthentication(username,password);
            SmtpAuth sa=new SmtpAuth();
            sa.getuserinfo(username,password);
            Session sessionDLT= Session.getInstance(props,sa);
            // watch the mail commands go by to the mail server
            sessionDLT.setDebug(true);
                // Define message
            MimeMessage message = new MimeMessage(sessionDLT);
            message.setFrom(new InternetAddress(from));
            message.addRecipient(Message.RecipientType.TO, new InternetAddress(to));
            message.setSubject("Hello JavaMail");
            message.setSentDate(new Date());
            //message.setDataHandler(new javax.activation.DataHandler(new pipi.jaf.StringDataSource(body,"text/html")));
            //out.println("Hello JavaMail");
            //out.println("welcome to JavaMail");
            message.setDataHandler(new DataHandler(body,"text/html;charset=us-ascii"));
            //message.setText("Welcome to JavaMail");
            //message.setText(body);
            message.setContent("welcome","text/plain");
            //             message.saveChanges();            Transport transport = sessionDLT.getTransport("smtp");
         //   transport.connect(host, username, password);
            transport.send(message);
           // transport.send(message);
            //transport.sendMessage(message, message.getAllRecipients());
            //transport.close();
              out.println("this is  a test.");
            // Send message
   //         message.saveChanges();}catch(Exception e){
  out.println(e.getMessage());
}%>
附上一个类SmtpAuth
import java.util.Date;
import java.util.*;
import java.util.Hashtable;
import javax.activation.DataHandler;
import javax.activation.FileDataSource;
import javax.mail.*;
import javax.mail.internet.*;public class SmtpAuth extends javax.mail.Authenticator{
private String user,password;
public void getuserinfo(String getuser,String getpassword){
user=getuser;
password=getpassword;
}
protected javax.mail.PasswordAuthentication getPasswordAuthentication(){
return new  javax.mail.PasswordAuthentication(user,password);
}
}