public void unregisterPositionListener(@Nonnull String name) {
NamedEntry.validateName(name);
PositionListenerEntry positionListenerEntry;
if (positionListenerEntryByName == null
|| (positionListenerEntry = positionListenerEntryByName.remove(name)) == null) {
throw new IllegalArgumentException("Listener '" + name + "' is not registered.");
}
positionListenerEntries.remove(positionListenerEntry);
}
public void registerPositionListener(
@Nonnull PositionListener listener, @Nonnull String name, double priority) {
NamedEntry.validateName(name);
if (positionListenerEntryByName == null) {
positionListenerEntryByName = new HashMap<>(1);
positionListenerEntries = new TreeSet<>(PositionListenerEntry.comparator);
} else if (positionListenerEntryByName.containsKey(name)) {
throw new IllegalArgumentException("Listener '" + name + "' is already registered.");
}
PositionListenerEntry positionListenerEntry =
new PositionListenerEntry(name, priority, listener);
positionListenerEntryByName.put(name, positionListenerEntry);
positionListenerEntries.add(positionListenerEntry);
}
public boolean hasPositionListener(@Nonnull String name) {
NamedEntry.validateName(name);
return positionListenerEntryByName != null && positionListenerEntryByName.containsKey(name);
}