Send a mail using smtp server

Question

i'm new to java mail api
i'm using a machine which is in a network under a proxy server and a fire wall.our network has a smtp server.
i tried to send a amil using a smtp server.
my codes are
package mailtest;
import java.util.Properties;
import javax.mail.Session;
import javax.mail.internet.MimeMessage;
import javax.mail.internet.InternetAddress;
import javax.mail.MessagingException;
import java.io.*;
import javax.mail.Message;
import javax.mail.Transport;
public class FirstMail {
String mailServer;
String host;
public FirstMail() {
//global
mailServer="mail.smtp.host";
host="mail.informatics.lk";
// Get system properties
Properties myProperties=new Properties() ;
// Setup mail server
myProperties.put(mailServer,host) ;
myProperties.put("mail.smtp.auth", "true");
// Get session
Session myMailSession;
myMailSession=Session.getInstance(myProperties,null);
//myMailSession.setDebug(true);
// Define message
MimeMessage message=new MimeMessage(myMailSession);
// Set the from address
//try {
try {
message.setFrom(new InternetAddress("[email protected]","CHANAKA ARUNA"));
catch (UnsupportedEncodingException ex1) {
System.out.println("CAN NOT SEND FROM");
catch (MessagingException ex1) {
System.out.println("CAN NOT SEND FROM");
// Set the to address
try {
message.addRecipient(Message.RecipientType.TO, new InternetAddress("[email protected]"));
catch (MessagingException ex) {
System.out.println("CAN NOT SEND TO");
// Set the subject
try {
message.setSubject("RE:$$$$");
catch (MessagingException ex2) {
System.out.println("WRONG SUBJECT");
// Set the content
try {
message.setText("***chanaka***");
catch (MessagingException ex3) {
System.out.println("WRONG MESSAGE");
// Send message
try {
Transport.send(message);
System.out.println("MESSAGE SENT");
catch (MessagingException ex4) {
System.out.println("UNABLE TO SEND");
public static void main(String[] args) {
FirstMail firstMail1 = new FirstMail();
it was not work, but when i use the ip address of smtp server instead of mail.informatics.lk at
host="mail.informatics.lk";
it worked properly and i could get a mail to my yahoo address.
but i have seen some have used host name like
host="smtp.snet.yahoo.com";
how can i do it using yahoo smtp server.
also i want to know whethr i can use that our smtp server from a computer outside of the net work.
pls help me
txs lot.

Answer 1

Almost certainly, if you are behind a proxy server it will only be a proxy for HTTP traffic, and you will not be able to communicate with an SMTP server outside your network. But you have your own SMTP server so why would you want to?
If you have a proxy server and an SMTP server then there will be people responsible for supporting them. Talk to those people and ask them to give you the basic explanation of networking that you need.