assertEquals(0, registry.getSubscribersForTesting(String.class).size());

    registry.register(new StringSubscriber());
    assertEquals(1, registry.getSubscribersForTesting(String.class).size());

    registry.register(new StringSubscriber());
    assertEquals(2, registry.getSubscribersForTesting(String.class).size());

    registry.register(new ObjectSubscriber());
    assertEquals(2, registry.getSubscribersForTesting(String.class).size());

  }

  public void testNulls_interface() {
    tester.testNulls(AnInterface.class);
  }

  public void testNulls_abstractClass() {
    tester.testNulls(AnAbstractClass.class);
  }

  public void testNulls_enum() throws Exception {
    tester.testNulls(OneConstantEnum.class);
    tester.testNulls(NoConstantEnum.class);
    tester.testNulls(TimeUnit.class);
  }

import org.lastaflute.web.response.render.RenderData;

public class RenderDataUtil {

    public static void register(final RenderData data, final String key, final Object value) {
        if (value == null) {
            return;
        }

        if (value instanceof Entity) {
            data.register(key, BeanUtil.copyBeanToNewMap(value));
        } else {

        });
    }

    protected void searchPaging(final RenderData data, final SearchForm form) {
        RenderDataUtil.register(data, "webAuthenticationItems", webAuthenticationService.getWebAuthenticationList(webAuthPager)); // page navi
        RenderDataUtil.register(data, "displayCreateLink", !crawlingConfigHelper.getAllWebConfigList(false, false, false, null).isEmpty());
        // restore from pager

    protected ThreadLocal<LaJobRuntime> jobRuntimeLocal = new ThreadLocal<>();

    public void register(final ScheduledJob scheduledJob) {
        final JobManager jobManager = ComponentUtil.getJobManager();
        jobManager.schedule(cron -> register(cron, scheduledJob));
    }

    public void register(final LaCron cron, final ScheduledJob scheduledJob) {
        if (scheduledJob == null) {

        });
    }

    protected void searchPaging(final RenderData data, final SearchForm form) {
        RenderDataUtil.register(data, "requestHeaderItems", requestHeaderService.getRequestHeaderList(reqHeaderPager)); // page navi
        RenderDataUtil.register(data, "displayCreateLink", !crawlingConfigHelper.getAllWebConfigList(false, false, false, null).isEmpty());

        // restore from pager

  @CanIgnoreReturnValue
  public long copyTo(CharSink sink) throws IOException {
    checkNotNull(sink);

    Closer closer = Closer.create();
    try {
      Reader reader = closer.register(openStream());
      Writer writer = closer.register(sink.openStream());
      return CharStreams.copy(reader, writer);
    } catch (Throwable e) {
      throw closer.rethrow(e);
    } finally {
      closer.close();
    }
  }

    Closer closer = Closer.create();
    try {
      InputStream in = closer.register(openStream());
      return countBySkipping(in);
    } catch (IOException e) {
      // skip may not be supported... at any rate, try reading
    } finally {
      closer.close();
    }

    closer = Closer.create();
    try {
      InputStream in = closer.register(openStream());
      return ByteStreams.exhaust(in);

        });
    }

    protected void registerRolesAndLabels(final RenderData data) {
        RenderDataUtil.register(data, "labelSettingEnabled", fessConfig.isFormAdminLabelInConfigEnabled());
        RenderDataUtil.register(data, "roleTypeItems", roleTypeService.getRoleTypeList());
        RenderDataUtil.register(data, "labelTypeItems", labelTypeService.getLabelTypeList());
    }

            searchPaging(data, form);
        });
    }

    protected void searchPaging(final RenderData data, final SearchForm form) {
        RenderDataUtil.register(data, "searchLogItems", searchLogService.getSearchLogList(searchLogPager)); // page navi

        // restore from pager
        copyBeanToBean(searchLogPager, form, op -> op.include(CONDITION_FIELDS));
    }