in src/main/java/org/apache/sling/models/impl/ModelAdapterFactory.java [165:181]
public void put(ServletRequest request, Disposable registry) {
synchronized (callbacks) {
CombinedDisposable combinedDisposable = null;
Disposable current = callbacks.get(request);
if (current == null) {
callbacks.put(request, registry);
return;
} else if (current instanceof CombinedDisposable) {
combinedDisposable = (CombinedDisposable) current;
} else {
combinedDisposable = new CombinedDisposable();
combinedDisposable.add(current);
callbacks.put(request, combinedDisposable);
}
combinedDisposable.add(registry);
}
}