package nodebox.node;

import java.lang.ref.WeakReference;

import java.util.ArrayList;

import java.util.Iterator;

import java.util.List;

import java.util.concurrent.CopyOnWriteArrayList;

public class NodeEventBus {

public List<WeakReference<NodeEventListener>> listeners = new CopyOnWriteArrayList<WeakReference<NodeEventListener>>();

public void addListener(NodeEventListener l) {

listeners.add(new WeakReference<NodeEventListener>(l));

}

public boolean removeListener(NodeEventListener l) {

Iterator<WeakReference<NodeEventListener>> it = listeners.iterator();

WeakReference<NodeEventListener> toRemove = null;

while (it.hasNext()) {

WeakReference<NodeEventListener> ref = it.next();

if (l == ref.get()) {

toRemove = ref;

break;

}

}

if (toRemove != null) {

listeners.remove(toRemove);

return true;

}

return false;

}

public List<NodeEventListener> getListeners() {

List<NodeEventListener> ll = new ArrayList<NodeEventListener>();

for (WeakReference<NodeEventListener> ref : listeners) {

NodeEventListener l = ref.get();

if (l != null)

ll.add(l);

}

return ll;

}

public void send(NodeEvent event) {

for (WeakReference<NodeEventListener> ref : listeners) {

NodeEventListener l = ref.get();

if (l != null)

l.receive(event);

}

}

}