how to solve Host unknown exception - unknown-host

Question

when i try to execute this code ...It produces the hostunknownException....
import java.io.*;
import java.net.*;
import java.net.Socket;
public class SMTP
{
public static void main(String[] args) //throws Exception
{
String results = send("sender#somewhere.com", "localhost/localdomain", "Test Email", "<b>You got mail!</b>");
System.out.println(results);
}
public static String send(String from,String to,String subject, String message) //throws Exception
{
StringBuffer buffer = new StringBuffer();
try
{
Socket smtpSocket = new Socket("127.0.0.1",25);
DataOutputStream output = new DataOutputStream(smtpSocket.getOutputStream());
BufferedReader input =new BufferedReader(new InputStreamReader( new DataInputStream(smtpSocket.getInputStream())));
try
{
read(input, buffer);
send(output, "HELO localhost.localdomain\r\n", buffer);
read(input, buffer);
send(output, "MAIL FROM: " + from + "\r\n", buffer);
read(input, buffer);
send(output, "RCPT to: " + to + "\r\n", buffer);
read(input, buffer);
send(output, "DATA\r\n", buffer);
read(input, buffer);
send(output, "Subject: " + subject + "\r\n", buffer);
send(output, message, buffer);
send(output, "\r\n.\r\n", buffer);
read(input, buffer);
smtpSocket.close();
}
catch (IOException e)
{
System.out.println("Cannot send email as an error occurred.");
}
}
catch (Exception e)
{
System.out.println("Host unknown");
}
return buffer.toString();
}
private static void send(DataOutputStream output,String data,StringBuffer buffer) throws IOException
{
output.writeBytes(data);
buffer.append(data);
}
private static void read(BufferedReader br, StringBuffer buffer) throws IOException
{
int c;
while ((c = br.read()) != -1)
{
buffer.append((char) c);
if (c == '\n')
{
break;
}
}
}
}
Please help me.....i'm new to java...i trying to implement the simple mail transfer protocol...there is no compilation errors....when i try to execute this ...unknown host exception is produced....

Answer 1

You still need a smtp server running on your localhost. Like apache James. Or you could try using google ones for testing purpose.
Try with this mykong example