praktikum-holons/src/holeg/utility/events/Event.java

package holeg.utility.events;

import java.util.HashSet;
import java.util.Set;

public class Event {

  private final Set<Runnable> listeners = new HashSet<Runnable>();

  public void addListener(Runnable listener) {
    listeners.add(listener);
  }

  public void broadcast() {
    listeners.forEach(Runnable::run);
  }

  public void removeListener(Runnable listener) {
    listeners.remove(listener);
  }
}