code: private int selectTypes(Trigger<? super S> trigger) {
          Class<? extends Trigger> triggerClass = trigger.getClass();
  
          int types = 0;
  
          if (overridesOneMethod(triggerClass, INSERT_METHODS)) {
              types |= FOR_INSERT;
          }
  
          if (overridesOneMethod(triggerClass, UPDATE_METHODS)) {
              types |= FOR_UPDATE;
          }
  
          if (overridesOneMethod(triggerClass, DELETE_METHODS)) {
              types |= FOR_DELETE;
          }
  
          if (overridesMethod(triggerClass, AFTER_LOAD_METHOD)) {
              types |= FOR_LOAD;
          }
  
          return types;
      }
docs: Determines which operations the given trigger overrides.