在后台发送电子邮件时没有收到电子邮件正文和附件

Question

我正在尝试在后台发送电子邮件。一切都工作正常我也收到邮件但问题是我没有收到电子邮件正文和电子邮件中的附件。

我没有收到任何错误或任何异常，我收到邮件也在我的邮件ID，但只是问题是附件和电子邮件正文，在附件我试图从SD卡发送图像。那么以下代码中的问题是什么呢？任何人都可以提供帮助。

GMailSender.java

public class GMailSender extends javax.mail.Authenticator {

    private String mailhost = "smtp.gmail.com";
    private String user;
    private String password;
    private Session session;
    private Multipart _multipart;

    static {
        Security.addProvider(new JSSEProvider());
    }

    public GMailSender(String user, String password) {
        this.user = user;
        this.password = password;

        Properties props = new Properties();
        props.setProperty("mail.transport.protocol", "smtp");
        props.setProperty("mail.host", mailhost);
        props.put("mail.smtp.auth", "true");
        props.put("mail.smtp.port", "465");
        props.put("mail.smtp.socketFactory.port", "465");
        props.put("mail.smtp.socketFactory.class",
                "javax.net.ssl.SSLSocketFactory");
        props.put("mail.smtp.socketFactory.fallback", "false");
        props.setProperty("mail.smtp.quitwait", "false");

        session = Session.getDefaultInstance(props, this);
        _multipart = new MimeMultipart();
    }

    protected PasswordAuthentication getPasswordAuthentication() {
        return new PasswordAuthentication(user, password);
    }

    public synchronized void sendMail(String subject, String body,
            String sender, String recipients) throws Exception {
        MimeMessage message = new MimeMessage(session);
        DataHandler handler = new DataHandler(new ByteArrayDataSource(
                body.getBytes(), "text/plain"));
        message.setSender(new InternetAddress(sender));
        message.setSubject(subject);

        message.setDataHandler(handler);
        message.setContent(_multipart);
        if (recipients.indexOf(',') > 0)
            message.setRecipients(Message.RecipientType.TO,
                    InternetAddress.parse(recipients));
        else
            message.setRecipient(Message.RecipientType.TO, new InternetAddress(
                    recipients));
        Transport.send(message);

    }

    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);
    }

    public class ByteArrayDataSource implements DataSource {
        private byte[] data;
        private String type;

        public ByteArrayDataSource(byte[] data, String type) {
            super();
            this.data = data;
            this.type = type;
        }

        public ByteArrayDataSource(byte[] data) {
            super();
            this.data = data;
        }

        public void setType(String type) {
            this.type = type;
        }

        public String getContentType() {
            if (type == null)
                return "application/octet-stream";
            else
                return type;
        }

        public InputStream getInputStream() throws IOException {
            return new ByteArrayInputStream(data);
        }

        public String getName() {
            return "ByteArrayDataSource";
        }

        public OutputStream getOutputStream() throws IOException {
            throw new IOException("Not Supported");
        }
    }
}

JSSEProvider.java

public class JSSEProvider extends Provider {

    private static final long serialVersionUID = 1L;

    public JSSEProvider() {
        super("HarmonyJSSE", 1.0, "Harmony JSSE Provider");
        AccessController
                .doPrivileged(new java.security.PrivilegedAction<Void>() {
                    public Void run() {
                        put("SSLContext.TLS",
                                "org.apache.harmony.xnet.provider.jsse.SSLContextImpl");
                        put("Alg.Alias.SSLContext.TLSv1", "TLS");
                        put("KeyManagerFactory.X509",
                                "org.apache.harmony.xnet.provider.jsse.KeyManagerFactoryImpl");
                        put("TrustManagerFactory.X509",
                                "org.apache.harmony.xnet.provider.jsse.TrustManagerFactoryImpl");
                        return null;
                    }
                });
    }
}

Activity.java

Button mButton = (Button) findViewById(R.id.button1);
        mButton.setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(View arg0) {
                new sendEmail().execute();
            }
        });

和

public class sendEmail extends AsyncTask<Void, Void, String> {

        @Override
        protected String doInBackground(Void... params) {
            try {

                String subject = "Registration";
                String message = "Thank you for regestering with";
                String senderOfmail = "abcd@gmail.com";
                String receiver = "abcd@gmail.com";

                GMailSender sender = new GMailSender(
                        "abcd@gmail.com", "abcde12345");
                sender.sendMail(subject, message, senderOfmail, receiver);

                FileOutputStream outStream;
                File file;
                Bitmap bm = BitmapFactory.decodeResource(getResources(),
                        R.drawable.ic_launcher);
                String extStorageDirectory = Environment
                        .getExternalStorageDirectory().toString();

                file = new File(extStorageDirectory, "ic_launcher.PNG");
                try {
                    outStream = new FileOutputStream(file);
                    bm.compress(Bitmap.CompressFormat.PNG, 100, outStream);
                    outStream.flush();
                    outStream.close();
                } catch (FileNotFoundException e) {
                    e.printStackTrace();
                } catch (IOException e) {
                    e.printStackTrace();
                }

                try {
                    String fileName = file.toString().trim();
                    sender.addAttachment(fileName);
                } catch (Exception e) {
                    Toast.makeText(Signup.this,
                            "There was a problem sending the email.",
                            Toast.LENGTH_LONG).show();
                }
            } catch (Exception e) {
                Log.e("error", e.getMessage(), e);
                return "Email Not Sent";
            }
            return "Email Sent";
        }
    }