Receive email

package org.apache.commons.jci.examples.commandline;
 
import java.net.*;
import java.io.*;
 
public class DisplayMail {
 
    public static void main(String arg[]) {
	//
	// usage :
	// DisplayMail [mailServer] [user] [password]
	// (will not delete mail on the server)
	//
	try {
	    // connect on port 110 (POP3)
	    System.out.println("Connect to " + arg[0] + ":110");
	    Socket s = new Socket(arg[0], 110);
	    BufferedReader in = new BufferedReader(new InputStreamReader(s
		    .getInputStream()));
	    BufferedWriter out = new BufferedWriter(new OutputStreamWriter(s
		    .getOutputStream()));
	    DisplayMail mail = new DisplayMail();
	    mail.login(in, out, arg[1], arg[2]);
	    int i = mail.check(in, out);
	    if (i == 0) {
		System.out.println("No mail waiting.");
	    } else {
		for (int j = 1; j <= i; j++) {
		    String msg = mail.get(in, out, j);
		    System.out.println("*****");
		    System.out.println(msg);
		    System.out.println("*****");
		}
		//
		// If the mail was removed from the server
		// (see getMail()) then we must COMMIT with
		// the "QUIT" command :
		// send(out, "QUIT");
		//
	    }
	} catch (Exception e) {
	    e.printStackTrace();
	}
    }
 
    public String get(BufferedReader in, BufferedWriter out, int i)
	    throws IOException {
	String s = "";
	String t = "";
	send(out, "RETR " + i);
	while (((s = in.readLine()) != null) && (!(s.equals(".")))) {
	    t += s + "\n";
	}
	//
	// To remove the mail on the server :
	// send(out, "DELE "+i);
	// receive(in);
	//
	return t;
    }
 
    private void send(BufferedWriter out, String s) throws IOException {
	System.out.println(s);
	out.write(s + "\n");
	out.flush();
    }
 
    private String receive(BufferedReader in) throws IOException {
	String s = in.readLine();
	System.out.println(s);
	return s;
    }
 
    private void login(BufferedReader in, BufferedWriter out, String user,
	    String pass) throws IOException {
	receive(in);
	send(out, "HELO theWorld");
	receive(in);
	send(out, "USER " + user);
	receive(in);
	send(out, "PASS " + pass);
	receive(in);
    }
 
    private int check(BufferedReader in, BufferedWriter out) throws IOException {
	return getNumberOfMessages(in, out);
    }
 
    public int getNumberOfMessages(BufferedReader in, BufferedWriter out)
	    throws IOException {
	int i = 0;
	String s;
 
	send(out, "LIST");
	receive(in);
	while ((s = receive(in)) != null) {
	    if (!(s.equals("."))) {
		i++;
	    } else {
		return i;
	    }
	}
	return 0;
    }
}