assertTrue("Exception message should mention unregistered class: " + message,
                    message != null && (message.contains("not registered") || message.contains("Class is not registered")
                            || message.contains("unregistered")));
        }
    }

    /**
     * Test that all registered types work correctly.
     * This ensures our registration covers the common use cases.

    bus.unregister(catcher1);
    bus.post(EVENT);

    assertEquals(
        "Shouldn't catch any more events when unregistered.", expectedEvents, catcher1.getEvents());
    assertEquals("Two correct events should be delivered.", expectedEvents, catcher2.getEvents());

    assertThrows(IllegalArgumentException.class, () -> bus.unregister(catcher1));

    bus.unregister(catcher2);

    bus.unregister(catcher1);
    bus.post(EVENT);

    assertEquals(
        "Shouldn't catch any more events when unregistered.", expectedEvents, catcher1.getEvents());
    assertEquals("Two correct events should be delivered.", expectedEvents, catcher2.getEvents());

    assertThrows(IllegalArgumentException.class, () -> bus.unregister(catcher1));

    bus.unregister(catcher2);

            return OptionalThing.empty();
        }
    }

    /**
     * Unregisters a scheduled job from the job manager.
     *
     * @param scheduledJob the scheduled job to unregister
     * @throws ScheduledJobException if the job cannot be unregistered
     */
    public void unregister(final ScheduledJob scheduledJob) {
        try {

     */
    public boolean unregisterWitness(String registrationId) {
        MockRegistration removed = registrations.remove(registrationId);
        if (removed != null) {
            log.debug("Mock unregistered witness: {}", registrationId);
            return true;
        }
        return false;
    }

    /**
     * Get the number of active registrations
     *
     * @return the registration count

            if (!holder.closed) {
                holder.closed = true;
                totalReleased.incrementAndGet();
            }
            log.trace("Unregistered resource: {} ({})", resourceId, holder.resourceType);
        }
    }

    /**
     * Check for and report resource leaks
     */
    public void checkForLeaks() {
        if (!leakDetectionEnabled) {
            return;
        }

                    log.info("Successfully unregistered witness: {}", registration.getRegistrationId());
                } else {
                    String errorMsg = response != null ? response.getError() : "Response was null";
                    log.warn("Failed to unregister witness: {}", errorMsg);
                }

            } catch (Exception e) {

   */
  public void register(Object object) {
    subscribers.register(object);
  }

  /**
   * Unregisters all subscriber methods on a registered {@code object}.
   *
   * @param object object whose subscriber methods should be unregistered.
   * @throws IllegalArgumentException if the object was not previously registered.
   */

                WitnessUnregisterResponse response = rpcClient.unregister(request);
                
                if (response.isSuccess()) {
                    registrations.remove(registration.getRegistrationId());
                    listeners.remove(registration.getRegistrationId());
                    
                    log.info("Successfully unregistered witness: {}", 
                        registration.getRegistrationId());

- Fixed a bug where an API group's path was not unregistered from the API server's root paths when the group was deleted. ([#121283](https://github.com/kubernetes/kubernetes/pull/121283), [@tnqn](https://github.com/tnqn)) [SIG API Machinery and Testing]