for (Pin pin : listeners.keySet()) {
// iterate over all listener handler in the map entry
// and remove each listener handler instance
List<PinListener> lsnrs = listeners.get(pin);
for (int index = lsnrs.size() - 1; index >= 0; index--) {
PinListener listener = lsnrs.get(index);
removeListener(pin, listener);
}
}
}