org.apache.commons.mail.EmailException: Cannot find valid hostname

[Ed]

I'm using the library email of jakarta to send email, but in the method setHostName("") I don't know what I have to put there, and it returns me this

org.apache.commons.mail.EmailException: Cannot find valid hostname
for mail session.

[Peter]

you have to put your host name
I'll give you an example

  SimpleEmail email = new SimpleEmail();
  email.setHostName("mail.myserver.com");
  email.addTo("jdoe@somewhere.org", "John Doe");
  email.setFrom("me@apache.org", "Me");
  email.setSubject("Test message");
  email.setMsg("This is a simple test of commons-email");
  email.send();

[Jack]

Go to this page: Commons Email - Examples

[Jhovarie]

hey i tried this code i get some errors.

import org.apache.commons.mail.*;

public class Main{
    public static void main(String[]args) throws EmailException{
        Email email = new SimpleEmail();
        email.setHostName("smtp.gmail.com");
        email.setSmtpPort(587);
        email.setAuthenticator(new DefaultAuthenticator("user@gmail.com", "*******"));
        email.setTLS(true);
        email.setFrom("user@gmail.com");
        email.setSubject("TestMail");
        email.setMsg("This is a test mail ... :-)");
        email.addTo("reciever@live.com");
        email.send();
    }
}

run:
Exception in thread "main" java.lang.NoClassDefFoundError: javax/mail/Message
	at Main.main(Main.java:5)
Caused by: java.lang.ClassNotFoundException: javax.mail.Message
	at java.net.URLClassLoader$1.run(URLClassLoader.java:202)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:307)
	at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:248)
	... 1 more
Java Result: 1

is there some thing missing in my library?
i already add apache.commons.mail
commons-email-1.2.jar