Como enviar e-mail a partir da sua conta do google ou yahoo pelo javamail

/*
 * Created on 14/09/2005
 *
 * TODO To change the template for this generated file go to
 * Window - Preferences - Java - Code Style - Code Templates
 */
import java.util.Properties;
 
import javax.mail.Authenticator;
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;
 
/**
 * @author gaucho
 * 
 * TODO To change the template for this generated type comment go to Window -
 * Preferences - Java - Code Style - Code Templates
 */
public class NewTestGmail {
 
	private static final String SMTP_HOST_NAME = "gmail-smtp.l.google.com";
 
	private static final String SMTP_AUTH_USER = "[email removido]";
 
	private static final String SMTP_AUTH_PWD = "minhasenha";
 
	private static final String emailMsgTxt = "Please visit my project at ";
 
	private static final String emailSubjectTxt = "Order Confirmation Subject";
 
	private static final String emailFromAddress = "[email removido]";
 
	// Add List of Email address to who email needs to be sent to
	private static final String[] emailList = { "[email removido]" }; 
 
	public static void main(String args[]) throws Exception {
		NewTestGmail smtpMailSender = new NewTestGmail();
		smtpMailSender.postMail(emailList, emailSubjectTxt, emailMsgTxt,
				emailFromAddress);
		System.out.println("Sucessfully Sent mail to All Users");
	}
 
	public void postMail(String recipients[], String subject, String message,
			String from) throws MessagingException {
		boolean debug = false;
		java.security.Security
				.addProvider(new com.sun.net.ssl.internal.ssl.Provider());
 
		//Set the host smtp address
		Properties props = new Properties();
		props.put("mail.transport.protocol", "smtp");
		props.put("mail.smtp.starttls.enable","true");
		props.put("mail.smtp.host", SMTP_HOST_NAME);
		props.put("mail.smtp.auth", "true");
 
		Authenticator auth = new SMTPAuthenticator();
		Session session = Session.getDefaultInstance(props, auth);
 
		session.setDebug(debug);
 
		// create a message
		Message msg = new MimeMessage(session);
 
		// set the from and to address
		InternetAddress addressFrom = new InternetAddress(from);
		msg.setFrom(addressFrom);
 
		InternetAddress[] addressTo = new InternetAddress[recipients.length];
		for (int i = 0; i < recipients.length; i++) {
			addressTo[i] = new InternetAddress(recipients[i]);
		}
		msg.setRecipients(Message.RecipientType.TO, addressTo);
 
		// Setting the Subject and Content Type
		msg.setSubject(subject);
		msg.setContent(message, "text/plain");
		Transport.send(msg);
	}
 
	/**
	 * SimpleAuthenticator is used to do simple authentication when the SMTP
	 * server requires it.
	 */
	private class SMTPAuthenticator extends javax.mail.Authenticator {
 
		public PasswordAuthentication getPasswordAuthentication() {
			String username = SMTP_AUTH_USER;
			String password = SMTP_AUTH_PWD;
			return new PasswordAuthentication(username, password);
		}
	}
}