使用 javamail 连接 SMTP 时的错误

Question

这是我发送一个邮件使用的代码：

public String get_subject() {
        return _subject;
    }
    public void set_subject(String _subject) {
        this._subject = _subject;
    }
    public Mail() {                 
        _host = "mail.messagingengine.com";    
    _port = "587";  
        _sport = "587"; 
        _user = ""; // username
        _pass = ""; // password
        _from = ""; // email sent from
        _subject = ""; // email subject
        _body = ""; // email body
        _debuggable = false; // debug mode on or off - default off
        _auth = true; // smtp authentication - default on
        _multipart = new MimeMultipart();
        // There is something wrong with MailCap, javamail can not find a
        // handler for the multipart/mixed part, so this bit needs to be added.
        MailcapCommandMap mc = (MailcapCommandMap) CommandMap.getDefaultCommandMap();
        mc.addMailcap("text/html;; x-java-content-handler=com.sun.mail.handlers.text_html");
        mc.addMailcap("text/xml;; x-java-content-handler=com.sun.mail.handlers.text_xml");
        mc.addMailcap("text/plain;; x-java-content-handler=com.sun.mail.handlers.text_plain");
        mc.addMailcap("multipart/*;; x-java-content-handler=com.sun.mail.handlers.multipart_mixed");
        mc.addMailcap("message/rfc822;; x-java-content-handler=com.sun.mail.handlers.message_rfc822");
        CommandMap.setDefaultCommandMap(mc);
    }
    public Mail(String user, String pass) {
        this();
        _user = user;
        _pass = pass;
    }
    public boolean send() throws Exception {
        Properties props = _setProperties();
        if (!_user.equals("") && !_pass.equals("") && _to.length > 0 && !_from.equals("") && !_subject.equals("")
                && !_body.equals("")) {
            Session session = Session.getInstance(props, this);
            MimeMessage msg = new MimeMessage(session);
            msg.setFrom(new InternetAddress(_from));
            InternetAddress[] addressTo = new InternetAddress[_to.length];
            for (int i = 0; i < _to.length; i++) {
                addressTo[i] = new InternetAddress(_to[i]);
            }
            msg.setRecipients(MimeMessage.RecipientType.TO, addressTo);
            msg.setSubject(_subject);
            msg.setSentDate(new Date());
            // setup message body
            BodyPart messageBodyPart = new MimeBodyPart();
            messageBodyPart.setText(_body);
            _multipart.addBodyPart(messageBodyPart);
            // Put parts in message
            msg.setContent(_multipart);
            Transport.send(msg);
            return true;
        } else {
            return false;
        }
    }
    public void addAttachment(String filename) throws Exception {
        BodyPart messageBodyPart = new MimeBodyPart();
        DataSource source = new FileDataSource(filename);
        messageBodyPart.setDataHandler(new DataHandler(source));
        messageBodyPart.setFileName(filename);

        _multipart.addBodyPart(messageBodyPart);
    }
    @Override
    public PasswordAuthentication getPasswordAuthentication() {
        return new PasswordAuthentication(_user, _pass);
    }
    private Properties _setProperties() {
        Properties props = new Properties();

        props.put("mail.messagingengine.com", _host);
        // mail.messagingengine.com

        if (_debuggable) {
            props.put("mail.debug", "true");
        }
        if (_auth) {
            props.put("mail.smtp.auth", "true");
        }
        props.put("mail.smtp.port", _port);
        props.put("mail.smtp.socketFactory.port", _sport);
        props.put("mail.smtp.socketFactory.class", "javax.net.ssl.SSLSocketFactory");
        props.put("mail.smtp.socketFactory.fallback", "false");
        return props;
    }
    // the getters and setters
    public String getBody() {
        return _body;
    }
    public void setBody(String _body) {
        this._body = _body;
    }
    // more of the getters and setters …..
}

在命令 transport.send(msg);后出现的错误：

javax.mail.MessagingException: Could not connect to SMTP host: mail.messagingengine.com, port: 587;
  nested exception is:
    javax.net.ssl.SSLHandshakeException: javax.net.ssl.SSLProtocolException: SSL handshake aborted: ssl=0x1f81518: Failure in SSL library, usually a protocol error
error:140770FC:SSL routines:SSL23_GET_SERVER_HELLO:unknown protocol (external/openssl/ssl/s23_clnt.c:683 0x4025bc93:0x00000000)

Answer 1

下面的代码希望能给你帮助：

public class Mail extends javax.mail.Authenticator { 
  private String _user; 
  private String _pass; 
  private String[] _to; 
  public String[] get_to() {
    return _to;
}
public void set_to(String[] _to) {
    this._to = _to;
}
public String get_from() {
    return _from;
}
public void set_from(String _from) {
    this._from = _from;
}
public String get_subject() {
    return _subject;
}
public void set_subject(String _subject) {
    this._subject = _subject;
}
private String _from; 
  private String _port; 
  private String _sport; 
  private String _host; 
  private String _subject; 
  private String _body; 
  private boolean _auth; 
  private boolean _debuggable; 
  private Multipart _multipart; 
  public Mail() { 
    _host = "mail.messagingengine.com"; // default smtp server 
    _port = "465"; // default smtp port 
    _sport = "465"; // default socketfactory port 
    _user = ""; // username 
    _pass = ""; // password 
    _from = ""; // email sent from 
    _subject = ""; // email subject 
    _body = ""; // email body 
    _debuggable = false; // debug mode on or off - default off 
    _auth = true; // smtp authentication - default on 
    _multipart = new MimeMultipart(); 
    // There is something wrong with MailCap, javamail can not find a handler for the multipart/mixed part, so this bit needs to be added. 
    MailcapCommandMap mc = (MailcapCommandMap) CommandMap.getDefaultCommandMap(); 
    mc.addMailcap("text/html;; x-java-content-handler=com.sun.mail.handlers.text_html"); 
    mc.addMailcap("text/xml;; x-java-content-handler=com.sun.mail.handlers.text_xml"); 
    mc.addMailcap("text/plain;; x-java-content-handler=com.sun.mail.handlers.text_plain"); 
    mc.addMailcap("multipart/*;; x-java-content-handler=com.sun.mail.handlers.multipart_mixed"); 
    mc.addMailcap("message/rfc822;; x-java-content-handler=com.sun.mail.handlers.message_rfc822"); 
    CommandMap.setDefaultCommandMap(mc); 
  } 
  public Mail(String user, String pass) { 
    this(); 
    _user = user; 
    _pass = pass; 
  } 
  public boolean send() throws Exception { 
    Properties props = _setProperties(); 

    if(!_user.equals("") && !_pass.equals("") && _to.length > 0 && !_from.equals("") && !_subject.equals("") && !_body.equals("")) { 
      Session session = Session.getInstance(props, this); 
      MimeMessage msg = new MimeMessage(session); 
      msg.setFrom(new InternetAddress(_from)); 
      InternetAddress[] addressTo = new InternetAddress[_to.length]; 
      for (int i = 0; i < _to.length; i++) { 
        addressTo[i] = new InternetAddress(_to[i]); 
      } 
      msg.setRecipients(MimeMessage.RecipientType.TO, addressTo); 
      msg.setSubject(_subject); 
      msg.setSentDate(new Date()); 
       // setup message body 
      BodyPart messageBodyPart = new MimeBodyPart(); 
      messageBodyPart.setText(_body); 
      _multipart.addBodyPart(messageBodyPart); 
       // Put parts in message 
      msg.setContent(_multipart); 
      // send email 
      Transport.send(msg); 
       return true; 
    } else { 
      return false; 
    } 
  } 
  public void addAttachment(String filename) throws Exception { 
    BodyPart messageBodyPart = new MimeBodyPart(); 
    DataSource source = new FileDataSource(filename); 
    messageBodyPart.setDataHandler(new DataHandler(source)); 
    messageBodyPart.setFileName(filename); 
    _multipart.addBodyPart(messageBodyPart); 
  } 
  @Override 
  public PasswordAuthentication getPasswordAuthentication() { 
    return new PasswordAuthentication(_user, _pass); 
  } 
  private Properties _setProperties() { 
    Properties props = new Properties(); 
    props.put("mail.smtp.host", _host); 
    if(_debuggable) { 
      props.put("mail.debug", "true"); 
    } 
    if(_auth) { 
      props.put("mail.smtp.auth", "true"); 
    } 
    props.put("mail.smtp.port", _port); 
    props.put("mail.smtp.socketFactory.port", _sport); 
    props.put("mail.smtp.socketFactory.class", "javax.net.ssl.SSLSocketFactory"); 
    props.put("mail.smtp.socketFactory.fallback", "false"); 
    return props; 
  } 
  // the getters and setters 
  public String getBody() { 
    return _body; 
  } 
   public void setBody(String _body) { 
    this._body = _body; 
  } 
  // more of the getters and setters ….. 
} 

我想错误是在：

_port = "465"; // default smtp port 
_sport = "465"; // default socketfactory port 

和这一行：

props.put("mail.messagingengine.com", _host);