Generating activation code

[yalgashev]

Hi, dear friends!!! I'm new in java
I'm realizing new Certificate Authorization.
Now I'm in activation code step.
I've a problem with realizing activation code.
As I understand, activation code works like this:
1) I get a id+users e-mail, and got a digest with MD5 or SHA1
2) I save the digest to base and send it to user
3) User gets a digest and resends it to me
4) I check: if my digest and digest, which user send are equal, then I believe that, there are such as e-mail, and I send some another information via user's e-mail.

Friend, firstly, sorry for my poor English.
Second, please let me now, am I understand validating e-mail right? If there are something wrong, please advice me.

Thank for attention and advices! :)

[Petr]

Hi
I think that is correct actions. But this is not Java. This is just design app.

[yalgashev]

Yes, it's not java. I'm realizing all my application in java, that's why I thought may be java developers will help.
Now, I've a such as question: how do I send messages to some e-mail via java application? Is there any solution? Thanks. :)

[yalgashev]

I googled and found this: Send email with JavaMail - Real's Java How-to and this: Sending Email From Your Application Using Java Mail
May be they'll help...

[yalgashev]

Guys, I found solution! I didn't it myself: JavaMail API – Sending email via Gmail SMTP example
I choose second, works! :)
Here is my code:

import java.util.Properties;
import javax.mail.Message;
import javax.mail.MessagingException;
import javax.mail.PasswordAuthentication;
import javax.mail.Session;
import javax.mail.Transport;
import javax.mail.internet.InternetAddress;
import javax.mail.internet.MimeMessage;
 
public class msgsendsample
{
    public static void main( String[] args )
    {	
    	Properties props = new Properties();
    	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 session = Session.getDefaultInstance(props,
	new javax.mail.Authenticator() 
	{
		protected PasswordAuthentication getPasswordAuthentication()
		{ return new PasswordAuthentication(username, password);	}
	});		
 
    	try {
 
            Message message = new MimeMessage(session);
	    message.setFrom(new InternetAddress("username@gmail.com"));
	    message.setRecipients(Message.RecipientType.TO, 
                        InternetAddress.parse("somebody@mail.org"));
	    message.setSubject("Hi!");
	    message.setText("This is me!");
 
	    Transport.send(message);
 
	    System.out.println("Done");
 
    	} catch (MessagingException e) {
    	    throw new RuntimeException(e);
    	}
    }
}

[yalgashev]

:confused:
Now I've to realize activation code app