EventBus

Simple Java EventBus.

Follow steps to start using EventBus. These steps are by example used in a Swing demo application in this project located in test -> com.jdotsoft.eventbus.demo.EventBusDemo

See also http://www.jdotsoft.com/EventBus.php

Step 1. Create BlueEvent class which extends base class Event. This class might have constructor with arguments, member variables, and any methods.

public class BlueEvent extends Event {
}

Step 2. Create BlueEventListener interface which extends base interface EventListener with method onBlue(BlueEvent e). This interface might have any methods declarations, however, only method which returns void with single argument BlueEvent will be invoked.

public interface BlueEventListener extends EventListener {
   void onBlue(BlueEvent event);
}

Step 3. Implement BlueEventListener (and other event listeners if required) in some class which will receive the BlueEvent event and register it:

public class BluePanel extends JPanel implements BlueEventListener {
  public BluePanel() {
    EventBus.getInstance().registerListeners(this);
  }
  @Override
  public void onBlue(BlueEvent event) {
    . . .
  }
}

Step 4. Fire event

eventBus.fire(new BlueEvent());
- or -
EventBus.getInstance().fire(new BlueEvent());

Step 5. Object BluePanel will receive event in listener BlueEventListener implementation onBlue(BlueEvent e).

EventBus object could be instantiated as EventBus eventBus = new EventBus(); in some class and passed to listeners. Use static EventBus.getInstance(); as an alternative.