Java 邮件：设置中文编码

Question

我通过gmail给自己发了一封中文邮件，我成功收到了下面的headers

当我通过javax.mail发送中文邮件时，在我的邮件浏览器中显示如下

失败邮件的header如下：

我的代码如下：

    public boolean send() throws TestReportingException, MessagingException
    {
        try
        {

            String encodingOptions = "text/plain; charset=UTF-8";

            Authenticator authenticator = new Authenticator()
            {
                // override the getPasswordAuthentication method
                protected PasswordAuthentication getPasswordAuthentication()
                {
                    return new PasswordAuthentication(username, password);
                }
            };

            // Create the mail session
            Session session = Session.getInstance(maileProperties, authenticator);

            MimeMessage mimeMessage = new MimeMessage(session);
            mimeMessage.setHeader("Content-Type", encodingOptions);

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

            // Set To: header field of the header.
            for (String s : toList)
            {
                if (null == s)
                {
                    throw new TestReportingException("Email address is null");
                }
                mimeMessage.addRecipients(Message.RecipientType.TO, InternetAddress.parse(s));
            }

            for (String s : ccList)
            {
                mimeMessage.addRecipients(Message.RecipientType.CC, InternetAddress.parse(s));
            }

            // Set Subject: header field
            mimeMessage.setSubject(subject,"UTF-8");

            // Create the message part
            //MimeBodyPart messageBodyPart = new MimeBodyPart();
        //    messageBodyPart.setContent(message, encodingOptions);

            // Create the message part
            MimeBodyPart messageBodyPart = new MimeBodyPart();
            mimeMessage.setHeader("Content-Type", encodingOptions);
            // Now set the actual message
            messageBodyPart.setText(message, "utf-8", "plain");

            // Now set the actual message
            //messageBodyPart.setText(message, "utf-8", "html");

            Multipart multipart = new MimeMultipart();

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



            // Part two is attachment
            if (null != attachmentSource)
            {
                messageBodyPart = new MimeBodyPart();

                messageBodyPart.setDataHandler(new DataHandler(attachmentSource));
                messageBodyPart.setFileName(attachmentSource.getName());
                multipart.addBodyPart(messageBodyPart);

            }

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


            // Send message
            //Transport.send(mimeMessage);

            SSm.getLogger().debug("Subject: "+mimeMessage.getSubject());




            Transport.send(mimeMessage);

            SSm.getLogger().info("\n\nSent message successfully....");

            clear();

            return true;

        }
        catch (MessagingException mex)
        {
            SSm.getLogger().error(mex.getMessage());
            throw mex;
        }
        catch (Exception e)
        {
            SSm.getLogger().error(e.getMessage(), e);
            throw new TestReportingException(e.getMessage(), e);
        }
    }

属性是：

主机=smtp.gmail.com
mail.smtp.auth=真
mail.smtp.starttls.enable=真mail.smtp.host=smtp.gmail.com
mail.smtp.port=587 mail.mime.charset=UTF-8

注意事项：文本在发送前没有损坏。 message.getSubject() 打印出干净的中文文本我猜我编码的方式有问题

编辑

调试输出如下：

DEBUG: setDebug: JavaMail version 1.5.5

DEBUG: getProvider() returning javax.mail.Provider[TRANSPORT,smtp,com.sun.mail.smtp.SMTPTransport,Oracle]

DEBUG SMTP: need username and password for authentication

DEBUG SMTP: useEhlo true, useAuth true

DEBUG SMTP: trying to connect to host "smtp.gmail.com", port 587, isSSL false

220 smtp.gmail.com ESMTP s20sm18171725pfg.11 - gsmtp

DEBUG SMTP: connected to host "smtp.gmail.com", port: 587

>

EHLO jake-yoga3.hitronhub.home

250-smtp.gmail.com at your service, [96.49.181.179]

250-SIZE 35882577

250-8BITMIME

250-STARTTLS

250-ENHANCEDSTATUSCODES

250-PIPELINING

250-CHUNKING

250 SMTPUTF8

DEBUG SMTP: Found extension "SIZE", arg "35882577"

DEBUG SMTP: Found extension "8BITMIME", arg ""

DEBUG SMTP: Found extension "STARTTLS", arg ""

DEBUG SMTP: Found extension "ENHANCEDSTATUSCODES", arg ""

DEBUG SMTP: Found extension "PIPELINING", arg ""

DEBUG SMTP: Found extension "CHUNKING", arg ""

DEBUG SMTP: Found extension "SMTPUTF8", arg ""

STARTTLS

220 2.0.0 Ready to start TLS

EHLO jake-yoga3.hitronhub.home

250-smtp.gmail.com at your service, [96.49.181.179]

250-SIZE 35882577

250-8BITMIME

250-AUTH LOGIN PLAIN XOAUTH2 PLAIN-CLIENTTOKEN OAUTHBEARER XOAUTH

250-ENHANCEDSTATUSCODES

250-PIPELINING

250-CHUNKING

250 SMTPUTF8

DEBUG SMTP: Found extension "SIZE", arg "35882577"

DEBUG SMTP: Found extension "8BITMIME", arg ""

DEBUG SMTP: Found extension "AUTH", arg "LOGIN PLAIN XOAUTH2 PLAIN-CLIENTTOKEN OAUTHBEARER XOAUTH"

DEBUG SMTP: Found extension "ENHANCEDSTATUSCODES", arg ""

DEBUG SMTP: Found extension "PIPELINING", arg ""

DEBUG SMTP: Found extension "CHUNKING", arg ""

DEBUG SMTP: Found extension "SMTPUTF8", arg ""

DEBUG SMTP: Attempt to authenticate using mechanisms: LOGIN PLAIN DIGEST-MD5 NTLM XOAUTH2

DEBUG SMTP: Using mechanism LOGIN

DEBUG SMTP: AUTH LOGIN command trace suppressed

DEBUG SMTP: AUTH LOGIN succeeded

DEBUG SMTP: use8bit false

MAIL FROM:

250 2.1.0 OK s20sm18171725pfg.11 - gsmtp

RCPT TO:

250 2.1.5 OK s20sm18171725pfg.11 - gsmtp

DEBUG SMTP: Verified Addresses

DEBUG SMTP: JSTONE@I-KODA.COM

DATA

354 Go ahead s20sm18171725pfg.11 - gsmtp

From: iKoda Report

To: JSTONE@I-KODA.COM

Message-ID: <1926337998.1.1488002481716@jake-yoga3>

Subject: =?UTF-8?B?QnZ4Y2Igw6TCuMKtIMOkwrjCrSDDpMK4wq0gw6TCuMKtIMOkwrjCrQ==?=

MIME-Version: 1.0

Content-Type: multipart/mixed;
   boundary="----=_Part_0_1855484302.1488002481637"

>

------=_Part_0_1855484302.1488002481637

Content-Type: text/plain; charset=utf-8

Content-Transfer-Encoding: base64

>

RGVhciBaeGN2LA0KDQpCdnhjYiDDpMK4wq0gw6TCuMKtIMOkwrjCrSDDpMK4wq0gw6TCuMKtw6TC

uMKtIMOkwrjCrSDDpMK4wq0gw6TCuMKtIMOkwrjCrWh0dHBzOi8vd3d3Lmkta29kYS5jb20vZGVs

aXZlcnkvZHNmcj91ZnQ9MTAxMjc3MCZjPTEwMTI3NjTDpMK4wq0gw6TCuMKtIMOkwrjCrSDDpMK4

wq0gw6TCuMKt

------=_Part_0_1855484302.1488002481637--

.

250 2.0.0 OK 1488002489 s20sm18171725pfg.11 - gsmtp

DEBUG SMTP: message successfully delivered to mail server

QUIT

221 2.0.0 closing connection s20sm18171725pfg.11 - gsmtp

[INFO] "jake.app" com.ikoda.service.utilities.EmailOut.send(EmailOut.java:256) 01:27:

>

Sent message successfully....

>

Answer 1

我找到问题了。问题不在电子邮件 class 中，仅与 javamail 无关。（所以上面的代码是正确的）

问题在于从我的控制器中 Spring 的 MessageBundle 的热连线实例中提取文本。

我错误地使用了以下代码，以便我的日志记录 class 可以记录从消息包中提取的字符串。

byte[] barray =messageSource.getMessage(code, null, LocaleContextHolder.getLocale()).getBytes(Charset.forName("UTF-8"));
    String s = new String(barray);

Log4j 可以读取主题和消息中的字符串（由 StringBuilder 构建），这让我相信字符串是正确的 UTF-8。但是，javax.mail在传输中出现乱码。

我应该做的是：

messageSource.getMessage(code, null, LocaleContextHolder.getLocale())

现在我的记录器只收到 ???，但电子邮件发送正常。

所以，保持简单愚蠢。

Java 邮件：设置中文编码

Java Mail: Setting Chinese Encoding

java

jakarta-mail

utf-8