server/client program

[Abigail Decan]

i pretty much re-typed the code from the oracle tutorial for sockets, but somehow it's not working.

i ran with

java Server 7
java Client localhost 7

with two consoles open.
i entered an input string for the Client console, but i'm not getting any echoes back.

i've checked and rechecked but i can't find what's missing.

Client.java

import java.io.*;
import java.net.*;


public class Client{
	public static void main(String[] args){
		// get arguments
		String host = args[0];
		int port = Integer.parseInt(args[1]);
		
		// open connection
		try{
			Socket s = new Socket(host,  port);
			
			// open i/o streams
			PrintWriter w = new PrintWriter(s.getOutputStream()); // write to socket
			BufferedReader user = new BufferedReader(new InputStreamReader(System.in)); // read from console
			BufferedReader r = new BufferedReader(new InputStreamReader(s.getInputStream()));// read from socket
			
			// read input from user
			String str = user.readLine(); // user input
			String echo; // echoed string
			while(str != null){
				// write to socket
				w.println(str);
				System.out.println("written to socket");
				// read echo from socket
				echo = r.readLine();
				System.out.println("read from socket");
				// print echo
				System.out.println("echo: " + echo);
				
				// update string
				str = user.readLine();
			}			
		}
		catch(UnknownHostException ex){
			System.err.println(ex);
			System.exit(1);
		} catch(IOException ex){
			System.err.println(ex);
			System.exit(1);
		} 
	
	}
}

Server.java

import java.io.*;
import java.net.*;

public class Server{
	public static void main(String[] args){
		// get arguments
		int port = Integer.parseInt(args[0]);
		
		try{
			// create socket
			ServerSocket s = new ServerSocket(port);
			
			// connect
			Socket c = s.accept();
			
			// i/o objects
			BufferedReader in = new BufferedReader(new InputStreamReader(c.getInputStream()));// read from socket
			PrintWriter w = new PrintWriter(c.getOutputStream(), true);// write to socket
			System.out.println("hello from server");
			String str = in.readLine();// input string
			System.out.println("a" + str);
			while(str != null){
				w.println(str);
				System.out.println(str);
				str = in.readLine();
			}
		
		}
		catch(IOException ex){
			System.err.println(ex);
		}
	}

}

the original codes are below:
http://docs.oracle.com/javase/tutorial/networking/sockets/examples/EchoClient.java
http://docs.oracle.com/javase/tutorial/networking/sockets/examples/EchoServer.java

[Paul Clapham]

I would suggest starting with an exact copy of the tutorial classes, and see if they work.

And anyway if you changed something in those tutorial classes, that's probably what broke them. You would be in a much better place to tell what you changed than we would.