Why can't i send email from my servlet and getting java.security.AccessControlException?

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Why can't i send email from my servlet?

I am using google app engine. I want to send email from my servlet. i am using following code:

 String to[] = {"mygmail@gmail.com"};
            String host = "smtp.gmail.com";
            String username = "mygmail@gmail.com";
            String password = "password";
            Properties props = new Properties();
            props.put("mail.smtps.auth", "true");
            props.put("mail.smtp.starttls.enable", "true");
            props.put("mail.smtp.host", host);
            props.put("mail.smtp.user", username);
            props.put("mail.smtp.password", password);
            props.put("mail.smtp.port", "587");
            props.put("mail.smtp.auth", "true");
            // ...
            Session session = Session.getInstance(props);
            MimeMessage msg = new MimeMessage(session);
            // set the message content here
            msg.setFrom(new InternetAddress(username,"Me"));
            msg.setSubject("Testing");
            msg.setText("Testing...");
            Address[] addresses = new Address[to.length];
            for (int i = 0; i < to.length; i++) {
                Address address = new InternetAddress(to[i]);               
                addresses[i] = address;
                // Add the given addresses to the specified recipient type.
                msg.addRecipient(Message.RecipientType.TO, new InternetAddress(to[i]));
            } 

            Transport t = session.getTransport("smtps");

            t.connect(host, username, password);
            t.sendMessage(msg, msg.getAllRecipients());
            t.close();

But i am getting following exception:

 Exception error: java.security.AccessControlException: access denied (java.net.SocketPermission smtp.gmail.com resolve)

Following are all imports of my servlet:

  import java.io.IOException;
  import java.io.PrintWriter;
  import java.util.List;
  import java.util.Properties;

  import javax.mail.Address;
  import javax.mail.BodyPart;
  import javax.mail.Message;
  import javax.mail.Multipart;
  import javax.mail.Session;
  import javax.mail.Transport;
  import javax.mail.internet.InternetAddress;
  import javax.mail.internet.MimeBodyPart;
  import javax.mail.internet.MimeMessage;
  import javax.mail.internet.MimeMultipart;
  import javax.servlet.http.HttpServlet;
  import javax.servlet.http.HttpServletRequest;
  import javax.servlet.http.HttpServletResponse;

Can anybody tell me whats the problem? Thanks in advance.

Answer 1

set following properties

        props.put("mail.smtp.starttls.enable", "true");
        props.put("mail.smtp.host", host);
        props.put("mail.smtp.user", username);
        props.put("mail.smtp.password", password);
        props.put("mail.smtp.port", "587");
        props.put("mail.smtp.auth", "true");

Answer 2

Let's go.

In your servlet code you can add a Thread start. The email will be sent in another class and not in the servlet. Like this:

MailObj mo = new MailObj();
mo.setMsgText("text blah blah blah");
mo.setEmailSource("to@mail.com");
mo.setSubject("subject");
Runnable t1 = new MailClass(request, response, mo);
new Thread(t1).start();

The MailObj stores email necessary data, such as the address of who will receive the email, the email text and subject. (Very and very simple approach)

public class MailObj {

    private String emailSource;
    private String msgText;
    private String subject;
    // getters and setters...

}

The MailClass has to implement the Runnable interface, which tells you to Override the run() method.

public class MailClass implements Runnable {

    private MailObj mo;
    HttpServletRequest req;
    HttpServletResponse res;

    public MailClass (HttpServletRequest request, HttpServletResponse response,
              MailObj mo){  //constructor
        this.req = request;
        this.res = response;
        this.mo = mo;

    }

    public void run() { // method of the Runnable interface
        try {
            sendEmail(req, res, mo);
        } catch (ServletException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }

    }

    public void sendEmail(HttpServletRequest request, HttpServletResponse response,                         MailObj mo) throws ServletException, IOException {

        Properties props = new Properties();
// here you set the host information (information about who is sending the email)
// in this case, who is sending the email is a gmail client...
        props.put("mail.smtp.host", "smtp.gmail.com");
        props.put("mail.smtp.socketFactory.port", "465");
        props.put("mail.smtp.socketFactory.class","javax.net.ssl.SSLSocketFactory");
        props.put("mail.smtp.auth", "true");
        props.put("mail.smtp.port", "465");

        Session ses2 = Session.getDefaultInstance(props,
                new javax.mail.Authenticator() {
                    protected PasswordAuthentication        getPasswordAuthentication() {
                        return new PasswordAuthentication(your_account,your_password);
                    }
                });

        try {


            Message msg = new MimeMessage(ses2); 

            msg.setFrom(new InternetAddress(email_to));
            msg.setRecipient(Message.RecipientType.TO, new InternetAddress(mo.getEmailSource()));
            msg.setSentDate(new Date());  
            msg.setSubject(mo.getSubject());  
            msg.setText(mo.getMsgText());

         // sending message (trying)  
            Transport.send(msg);  

        } catch (AddressException e) {
            e.printStackTrace();
        } catch (MessagingException e) {
            e.printStackTrace();
        }

Sending the email with a thread is a good way because you the email is sent "behind the runtime code", which means that the user WILL NOT wait for the email be sent. Sending an email takes a long time. Make some tests and you'll notice that. So use a thread is a good method to avoid long time waiting...

Hope it helps! =]

Answer 3

Here, have a look at my outlook client here; it is under the src folder. I struggled with the Javamail api for a long time and this seems to work well. Also, you should be using the Transport class statically to send a message, I am not sure if that is where your problem lies or not.

You should also be passing your properites object a class that extends STMPAuthenticator..