``````````
SMTP
=========
import java.io.*;
import java.net.*;
import java.util.*;
public class smtp
{

public static void main(String args[]) throws Exception
{
Socket s=null;
try{

s=new Socket("192.168.1.4",25);
System.out.println("Connected to smtp server");
}
catch(Exception e){}

PrintWriter out=new PrintWriter(s.getOutputStream(),true);
BufferedReader in=new BufferedReader(new InputStreamReader(s.getInputStream()));
BufferedReader sin=new BufferedReader(new InputStreamReader(System.in));
in.readLine();
out.println("helo");
in.readLine();
System.out.println("Enter ur mail id");
String sid=sin.readLine().trim();
out.println("mail from:"+sid);
System.out.println(in.readLine());
System.out.println("Enter receiver id");
String rid=sin.readLine().trim();
out.println("rcpt to:"+rid);
System.out.println(in.readLine());
System.out.println("Enter ur Message to send");
String msg=sin.readLine().trim();
out.println("data");
in.readLine();
out.println(msg);
out.println(".");
System.out.println(in.readLine());
System.out.println("mail sent");

}

}

```````````
POP3
=========
import java.io.*;
import java.net.*;
import java.util.*;
import java.lang.*;
class pop
{

public static void main(String args[]) throws Exception
{
Socket s=null;
try{

s=new Socket("192.168.1.4",110);
System.out.println("Connected to pop server");
}
catch(Exception e){}

PrintWriter out=new PrintWriter(s.getOutputStream(),true);
BufferedReader in=new BufferedReader(new InputStreamReader(s.getInputStream()));
BufferedReader sin=new BufferedReader(new InputStreamReader(System.in));
System.out.println(in.readLine());
System.out.println("Enter ur mail id");
String sid=sin.readLine().trim();
System.out.println(sid);
out.println("user "+sid);
System.out.println(in.readLine());
System.out.println("Enter ur Password");
String pwd=sin.readLine().trim();
out.println("pass "+pwd);
System.out.println(in.readLine());
System.out.println("Mail in INBOX");
out.println("list");
String str;
while((str=in.readLine())!=null)
{
if(!str.startsWith("."))
System.out.println(str);
else
break;
}

System.out.println("Enter mail No: ");
String mailno=sin.readLine();
out.println("retr "+mailno);
System.out.println(in.readLine());
while((str=in.readLine())!=null)
{
if(!str.startsWith("."))
System.out.println(str);
else
break;

}

System.out.println();
}

}