waiter2.join();
  }

  public void testRemoveWaiter_polling() throws Exception {
    AbstractFuture<String> future = new AbstractFuture<String>() {};
    WaiterThread waiter = new WaiterThread(future);
    waiter.start();
    waiter.awaitWaiting();
    PollingThread poller = new PollingThread(future);
    poller.start();
    PollingThread poller2 = new PollingThread(future);
    poller2.start();

   ([#121946](https://github.com/kubernetes/kubernetes/pull/121946), [@liggitt](https://github.com/liggitt))

public class CommandExecutionExceptionTest extends UnitFessTestCase {

    public void test_constructor_withMessage() {
        // Test constructor with message only
        String message = "Command execution failed";
        CommandExecutionException exception = new CommandExecutionException(message);

        assertNotNull(exception);
        assertEquals(message, exception.getMessage());
        assertNull(exception.getCause());

 * at one time; if a value is not available to be edited then [edit] will return null.
 *
 *  * When an entry is being **created** it is necessary to supply a full set of values; the empty
 *    value should be used as a placeholder if necessary.
 *
 *  * When an entry is being **edited**, it is not necessary to supply data for every value; values
 *    default to their previous value.
 *

    public Integer crudMode;

    /**
     * The unique identifier of the failure URL record being edited.
     * This is a required field for identifying which failure record to update.
     */
    @Required
    @Size(max = 1000)
    public String id;

    /**
     * The URL that failed during crawling.
     * This is a required field containing the actual URL that encountered an error.
     */
    @Required

    protected void handleFileUploadException(final FileUploadException e) throws ServletException {
        // suppress logging because it can be caught by logging filter
        //log.error("Failed to parse multipart request", e);
        throw new ServletException("Failed to upload the file.", e);
    }

    // ===================================================================================

     *     state with the exception of {@linkplain State#FAILED FAILED} and {@linkplain
     *     State#TERMINATED TERMINATED}.
     */
    public void terminated(State from) {}

    /**
     * Called when the service transitions to the {@linkplain State#FAILED FAILED} state. The
     * {@linkplain State#FAILED FAILED} state is a terminal state in the transition diagram.

        case NEW:
        case TERMINATED:
          throw new IllegalStateException("Failed while in state:" + previous, cause);
        case RUNNING:
        case STARTING:
        case STOPPING:
          snapshot = new StateSnapshot(FAILED, false, cause);
          enqueueFailedEvent(previous, cause);
          break;
        case FAILED:
          // Do nothing
          break;
      }
    } finally {

     * {@linkplain State#TERMINATED terminated} or {@linkplain State#FAILED failed}.
     */
    public void stopped() {}

    /**
     * Called when a component service has {@linkplain State#FAILED failed}.
     *
     * @param service The service that failed.
     */
    public void failure(Service service) {}
  }

  /**

            reload(updater, curlResponse.getContentAsStream());
        } catch (final IOException e) {
            throw new DictionaryException("Failed to parse " + path, e);
        }
    }

    /**
     * Reloads the character mapping items from the provided input stream.
     * Parses mapping rules in the format: input1,input2,... => output
     *