public IObservableSet getKnownElements() {
if (delegate == null) {
return null;
}
if (delegate instanceof ObservableSetTreeContentProvider) {
ObservableSetTreeContentProvider contentProvider = (ObservableSetTreeContentProvider) delegate;
return contentProvider.getKnownElements();
}
if (delegate instanceof ObservableListTreeContentProvider) {
ObservableListTreeContentProvider contentProvider = (ObservableListTreeContentProvider) delegate;
return contentProvider.getKnownElements();
}
throw new IllegalStateException();
}