code: public Set<SuppressedEvent> getSuppressedEvents() {
          if (this.suppressedEvents == null) {
              return Collections.emptySet();
          }
          return Collections.unmodifiableSet(this.suppressedEvents);
      }
docs: Gets a read-only set of the suppressed events that have been registered
  at this event using {@link #addSuppressedEvent(SuppressedEvent)}.
  
  @return The suppressed events.