brug af ekstern variable i java

jeg sidder og roder med en simple opgave i java

jeg sidder med 3 filer ... KKMultiServer.java som gernere flere KKMultiServerThread(tråde) som alle bruger en KnockKnockProtocol

i KKMultiServeren laver jeg et en liste med varible
        public List nameList = new List();
som jeg ønsker at tilføre nogle værdier i protokollen (ok not nice men det kommer til at virke)

dvs noget nameList.add(nytNavn);
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import java.net.*;
import java.io.*;

public class KKMultiServer {

        public List nameList = new List();

    public static void main(String[] args) throws IOException {
        ServerSocket serverSocket = null;
        boolean listening = true;

        try {
            serverSocket = new ServerSocket(4444);
        } catch (IOException e) {
            System.err.println("Could not listen on port: 4444.");
            System.exit(-1);
        }

        while (listening)
        new KKMultiServerThread(serverSocket.accept()).start();
        serverSocket.close();
    }
}

-------------------------------------------------------------
import java.net.*;
import java.io.*;
import java.awt.List;

public class KKMultiServerThread extends Thread {
    private Socket socket = null;


    public KKMultiServerThread(Socket socket) {
    super("KKMultiServerThread");
    this.socket = socket;
    }

    public void run() {

    try {
        PrintWriter out = new PrintWriter(socket.getOutputStream(), true);
        BufferedReader in = new BufferedReader(
                    new InputStreamReader(
                    socket.getInputStream()));

        String inputLine, outputLine;
        KnockKnockProtocol kkp = new KnockKnockProtocol();
        outputLine = kkp.processInput(null);
        out.println(outputLine);

        while ((inputLine = in.readLine()) != null) {
        outputLine = kkp.processInput(inputLine);
        out.println(outputLine);
        if (outputLine.equals("Bye"))
            break;
        }
        out.close();
        in.close();
        socket.close();

    } catch (IOException e) {
        e.printStackTrace();
    }
    }
}

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

public class KnockKnockProtocol {
    private static final int WAITING = 0;
    private static final int LogIn = 1;
    private static final int AllFine = 2;
    private static final int ANOTHER = 3;

    private static final int NUMJOKES = 5;

    private int state = WAITING;
    private int currentJoke = 0;

    private String[] clues = { "Turnip", "Little Old Lady", "Atch", "Who", "Who" };
    private String[] answers = { "Turnip the heat, it's cold in here!",
                                "I didn't know you could yodel!",
                                "Bless you!",
                                "Is there an owl in here?",
                                "Is there an echo in here?" };

    public String name = null;


    extern nameList ; <---  MIT GÆT



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


      if (state == WAITING) {
            theOutput = "What is your name?"; // client
            state = LogIn;
        } else

      if (state == LogIn) {
                  name = theInput;
                theOutput = "Welcome " + name + "\n To get all the names type 'list'";
                state = AllFine;
        } else

      if (state == AllFine && theInput.equalsIgnoreCase("list")) {
          theOutput = name ;
        } else



        if (state == LogIn) {
            if (theInput.equalsIgnoreCase("y")) {
                theOutput = "Knock! Knock!";
                if (currentJoke == (NUMJOKES - 1))
                    currentJoke = 0;
                else
                    currentJoke++;
                state = LogIn;
            } else {
                theOutput = "Bye.";
                state = WAITING;
            }
        }
        return theOutput;
    }
}