Code Won't Execute, Help Apreciated

[danielinthebed]

I'm making a Java download centre, the client can view a description of 3 items as provided by the server. I have a protocol to control what happens. The code however, won't compile properly. Here is what I've done so far. I believe the problem lies in the protocol program.

CLIENT

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

public class Client {

    public static void main(String[] args) throws IOException {

        Socket dcSocket = null;
        PrintWriter out = null;
        BufferedReader in = null;

        try {
            dcSocket = new Socket("localhost", 3330);
            out = new PrintWriter(dcSocket.getOutputStream(), true);
            in = new BufferedReader(new InputStreamReader(dcSocket.getInputStream()));
        } catch (UnknownHostException e) {
            System.err.println("Don't know about host");
            System.exit(1);
        } catch (IOException e) {
            System.err.println("Could not get IO for connection");
            System.exit(1);
        }

        BufferedReader stdIn = new BufferedReader(new InputStreamReader(System.in));
        String fromServer;
        String fromUser;

        while ((fromServer = in.readLine()) != null) {
            System.out.println("Server: " + fromServer);
            if (fromServer.equals("Bye")) {
                break;
            }

            fromUser = stdIn.readLine();
            if (fromUser != null) {
                System.out.println("Client: " + fromUser);
                out.println(fromUser);
            }

        }
        out.close();
        in.close();
        stdIn.close();
        dcSocket.close();
    }
}

SERVER

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

public class Server {

    public static void main(String[] args) throws IOException {

        ServerSocket serverSocket = null;
        try {
            serverSocket = new ServerSocket(3330); // Creates new ServerSocket object to listen on a specific port 
        } catch (IOException e) {
            System.err.println("Message 1");
            System.exit(1);
        }

        Socket clientSocket = null;
        try {
            clientSocket = serverSocket.accept(); // Accepts connection from a client 
        } catch (IOException e) {
            System.out.println("Message 2");
            System.exit(-1);
        }

        // Opens readers and writers on socket input and output stream
        PrintWriter out = new PrintWriter(clientSocket.getOutputStream(), true);
        BufferedReader in = new BufferedReader(new InputStreamReader(clientSocket.getInputStream()));
        String inputLine, outputLine;

        // Begin conversation with client program, creates protocol
        DownloadProtocol dp = new DownloadProtocol();
        outputLine = dp.processInput(null);
        out.println(outputLine);

        // Server reads and writes to socket 
        while ((inputLine = in.readLine()) != null) {
            outputLine = dp.processInput(inputLine);
            out.println(outputLine);
            if (outputLine.equals("N")) {
                break;
            }
        }
        
        out.close();
        in.close(); 
        clientSocket.close();
        serverSocket.close();
    }
}

PROTOCOL

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

public class DownloadProtocol {

    private int state = WAITING;
    private static final int WAITING = 1;
    private static final int REPLY = 2;
    private static final int CHOICE = 3;

    public String processInput(String theInput) {
        String theOutput = null;

        switch (state) {
            case 1: {
                theOutput = "Terms of reference. Do you accept? Y or N";
                if (theInput.equalsIgnoreCase("Y")) {
                    state = REPLY;
                }
            }
            case 2: {
                theOutput = "1. computer program 2. picture 3. e-book";
                state = CHOICE;
                int i = Integer.parseInt(theInput);
                switch (i) {
                    case 1: {
                        theOutput = "The program displays a message";
                        break;
                    }
                    case 2: {
                        theOutput = "The book is about";
                        break;
                    }
                    case 3: {
                        theOutput = "The picture shows";
                        break;
                    }
                    default: {
                        theOutput = "Invalid choice";
                        break;
                    }
                }

            }
        }
        return theOutput;
    }
}

[danielinthebed]

Netbeans errors

run:
Exception in thread "main" java.net.SocketException: Connection reset
at java.net.SocketInputStream.read(SocketInputStream. java:168)
at sun.nio.cs.StreamDecoder.readBytes(StreamDecoder.j ava:264)
at sun.nio.cs.StreamDecoder.implRead(StreamDecoder.ja va:306)
at sun.nio.cs.StreamDecoder.read(StreamDecoder.java:1 58)
at java.io.InputStreamReader.read(InputStreamReader.j ava:167)
at java.io.BufferedReader.fill(BufferedReader.java:13 6)
at java.io.BufferedReader.readLine(BufferedReader.jav a:299)
at java.io.BufferedReader.readLine(BufferedReader.jav a:362)
at Version_1.Client.main(Client.java:38)
Java Result: 1
BUILD SUCCESSFUL (total time: 0 seconds)

run:
Exception in thread "main" java.lang.NullPointerException
at Version_1.DownloadProtocol.processInput(DownloadPr otocol.java:25)
at Version_1.Server.main(Server.java:39)
Java Result: 1
BUILD SUCCESSFUL (total time: 4 seconds)

[Norm]

Please only post one thread per problem.
This is appears the same as
http://www.java-forums.org/advanced-...preciated.html