Server with a frontend GUI

Question

I have an application which maintains a database of objects as an ArrayList. I'm trying to add a sort of background server, which would accept requests for information from this database and provide responses, and also be able to store new objects in the database, then call a method in the main application to refresh the view.
I'm getting closer, but I've hit a wall. I can start a thread in the background which accepts connections, and because it's a separate thread the application is usable, but I'm not sure how to communicate with the application. In C#, I'd add an event and a delegate, but is there a Java equivalent to this? When a connection is accepted by the server thread, the thread needs to call methods in the main application for processing.
If someone could point me in the right direction or give me the name of what I want to I can find more information, I'd appreciate it.
Cheers

Answer 1

Echilon wrote:
When a connection is accepted by the server thread, the thread needs to call methods in the main application for processing.
If someone could point me in the right direction or give me the name of what I want to I can find more information, I'd appreciate it.
CheersHi,
This is implemented via callback; the MainClass implements an interface which your thread is passed to during the construction or a setter method
When the database connnection finishes, it invokes the interface method
ex:
public class MainClass implements Callback {
      * @param args
     public static void main(String[] args) {
          MainClass main = new MainClass();
          MainClass.MyThread thread= main.new MyThread(main);
          Thread t = new Thread(thread);
          t.start();
     public void doSomething() {
          System.out.println("I was called backed....");
   class MyThread implements Runnable {
       Callback callback;
       public MyThread(Callback callback){
            this.callback = callback;
       public void run() {
           try{ 
            Thread.currentThread().sleep(2000); // get connection
            System.out.println("Got connection...");
            callback.doSomething();// callback
           }catch(InterruptedException interEx) {
// and the interface
interface Callback {
       public void doSomething();
I hope this could help
Regards,
Alan Mehio
London,UK