Saving string from multiple clients on a server data structue

Question

I have a server which receives updates from multiple clients ( in this example, football scores which are updated periodically by the clients.)
When the server receives the scores it needs to store them and at certain time intervals send the complete list of scores to multiple terminals at various locations.
I am approaching this task in stages...
stage 1.
..create the clients and server ...test the clients can send the data and the server can receive the data and output to screen..
this is completed
stage 2...
a/ on the server side store the received scores in a data structure (ArrayList<String> is what I'm thinking.)
b/ periodically output all scores to the screen (maybe every 30 seconds) and empty the ArrayList..am looking at the Timer class for this part..
stage 3
create the monitors and output scores to monitors periodically..
======================================================
right now I'm at stage 2a ie trying to store the received scores in a data structure.
i've created a method saveScore in the StoreScore class which is called by the StoreScore run method...
The saveScore method creates an ArrayList and adds the score to it...
Question
does every thread create a new instance of storedScores and therefore the scores are stored in a multitude of data structures?
I think the answer is yes and if so then this is not the solution...
What I'm thinking is , as all scores can be outputted to the server screen via System.out.println, is there not a way of saving all these scores in a single data structure?
The code below is the server code..
any advice much appreciated....thank you
/*=============================================================== */
import java.io.*;
import java.net.*;
import java.util.*;
import java.util.concurrent.*;
class ScoresServer1{
final static int portNum = 1234; // any number > 1024
final static int numThreads = 10;
static ExecutorService pool;
public static void main(String[] args){
pool = Executors.newFixedThreadPool(numThreads);
System.out.println("Server running ...");
try{  
ServerSocket servesock = new ServerSocket(portNum);
// for service requests on port
while (true){ 
// wait for a service request on port portNum
Socket socket = servesock.accept();
// submit request to pool
pool.submit(new StoreScore(socket));
}catch(IOException e){}
class StoreScore implements Runnable {
BufferedReader reader;
Socket sock;
public StoreScore(Socket clientSOcket) {
try {
sock = clientSOcket;
InputStreamReader isReader = new InputStreamReader(sock.getInputStream());
reader = new BufferedReader(isReader);
} catch (Exception ex) { ex.printStackTrace(); }
public void run() {
String message;
try {
while ((message = reader.readLine()) != null) {
// System.out.println("latest score: " + message);
saveScore(message);
} catch (Exception ex) { ex.printStackTrace(); }
public void saveScore(String message){
     ArrayList<String> storedScores = new ArrayList<String>();
     storedScores.add(message);
     Iterator<String> t = storedScores.iterator();
          while(t.hasNext()){
               String s = t.next();
               System.out.println(s);
}

Answer 1

does every thread create a new instance of storedScores and therefore the scores are stored in a multitude of data structures?
I think the answer is yes and if so then this is not the solution...The answer is yes. However, threads can share data, if they were properly synchronized. You should read the threading tutorial before creating a lot of hard to debug mistakes.
[http://java.sun.com/docs/books/tutorial/essential/concurrency/]