private static <E extends Comparable<? super E>> SortedSet<E> nullCheckedTreeSet(E[] elements) {
    SortedSet<E> set = newTreeSet();
    for (E element : elements) {
      // Explicit null check because TreeSet wrongly accepts add(null) when empty.
      set.add(checkNotNull(element));
    }
    return set;
  }

  public static class ContiguousSetGenerator extends AbstractContiguousSetGenerator {
    @Override

        /*
         * 2010 - We no longer try a Node Status to get the
         * hostname because apparently some servers do not respond
         * anymore. I think everyone post Windows 98 will accept
         * an IP address as the tconHostName which is the principal
         * use of this method.
         */
        if (this.hostName.isUnknown()) {
            return getHostAddress();
        }

이러한 작업에는 다음이 포함됩니다.

* 작업을 수행한 후 전송되는 이메일 알림
    * 이메일 서버에 연결하고 이메일을 전송하는 것은 (몇 초 정도) "느린" 경향이 있으므로, 응답은 즉시 반환하고 이메일 알림은 백그라운드에서 전송하는 게 가능합니다.
* 데이터 처리:
    * 예를 들어 처리에 오랜 시간이 걸리는 데이터를 받았을 때 "Accepted" (HTTP 202)을 반환하고, 백그라운드에서 데이터를 처리할 수 있습니다.

## `백그라운드 작업` 사용

먼저 아래와 같이 `BackgroundTasks`를 임포트하고, `BackgroundTasks`를 _경로 작동 함수_ 에서 매개변수로 가져오고 정의합니다.

{* ../../docs_src/background_tasks/tutorial001.py hl[1,13] *}

        return doSelectEntity(xprepareCBAsPK(id), tp);
    }

    protected FileConfigCB xprepareCBAsPK(String id) {
        assertObjectNotNull("id", id);
        return newConditionBean().acceptPK(id);
    }

    protected <ENTITY extends FileConfig> OptionalEntity<ENTITY> doSelectOptionalByPK(String id, Class<? extends ENTITY> tp) {
        return createOptionalEntity(doSelectByPK(id, tp), id);
    }

        return doSelectEntity(xprepareCBAsPK(id), tp);
    }

    protected SearchLogCB xprepareCBAsPK(String id) {
        assertObjectNotNull("id", id);
        return newConditionBean().acceptPK(id);
    }

    protected <ENTITY extends SearchLog> OptionalEntity<ENTITY> doSelectOptionalByPK(String id, Class<? extends ENTITY> tp) {
        return createOptionalEntity(doSelectByPK(id, tp), id);
    }

   * href="https://url.spec.whatwg.org/#syntax-url-path-segment">URL path segments</a>. The returned
   * escaper escapes all non-ASCII characters, even though <a
   * href="https://url.spec.whatwg.org/#url-code-points">many of these are accepted in modern
   * URLs</a>. (<a href="https://url.spec.whatwg.org/#path-state">If the escaper were to leave these
   * characters unescaped, they would be escaped by the consumer at parse time, anyway.</a>)

        }

        @Test
        public void testConstructorWithMalformedUrl() {
            // Test that constructor throws MalformedURLException for completely invalid URL
            // Note: http:// URLs are actually accepted by the URL constructor but the protocol is changed to smb
            String invalidUrl = "not-a-valid-url";
            assertThrows(MalformedURLException.class, () -> new SmbFile(invalidUrl));
        }

        @Test

                context.terminal
                        .writer()
                        .println(messageBuilderFactory
                                .builder()
                                .warning("Values not accepted; not saving configuration.")
                                .build());
                return CANCELED;
            }
        }

        return OK;
    }

   *
   * @throws IOException if the request could not be executed due to cancellation, a connectivity
   *     problem or timeout. Because networks can fail during an exchange, it is possible that the
   *     remote server accepted the request before the failure.
   * @throws IllegalStateException when the call has already been executed.
   */
  @Throws(IOException::class)
  fun execute(): Response

  /**

        return doSelectEntity(xprepareCBAsPK(id), tp);
    }

    protected WebConfigCB xprepareCBAsPK(String id) {
        assertObjectNotNull("id", id);
        return newConditionBean().acceptPK(id);
    }

    protected <ENTITY extends WebConfig> OptionalEntity<ENTITY> doSelectOptionalByPK(String id, Class<? extends ENTITY> tp) {
        return createOptionalEntity(doSelectByPK(id, tp), id);
    }