*
   * <p>When methods such as {@code removeAll()} and {@code clear()} are called on the filtered map
   * or its views, only mappings whose keys satisfy the filter will be removed from the underlying
   * map.
   *
   * <p>The returned map isn't threadsafe or serializable, even if {@code unfiltered} is.
   *
   * <p>Many of the filtered map's methods, such as {@code size()}, iterate across every key/value

   *
   * <p>When methods such as {@code removeAll()} and {@code clear()} are called on the filtered map
   * or its views, only mappings whose keys satisfy the filter will be removed from the underlying
   * map.
   *
   * <p>The returned map isn't threadsafe or serializable, even if {@code unfiltered} is.
   *
   * <p>Many of the filtered map's methods, such as {@code size()}, iterate across every key/value

   *
   * <p><b>{@code Stream} equivalent:</b> {@link java.util.stream.Stream#filter Stream.filter}.
   */
  public static <E extends @Nullable Object> Collection<E> filter(
      Collection<E> unfiltered, Predicate<? super E> predicate) {
    if (unfiltered instanceof FilteredCollection) {
      // Support clear(), removeAll(), and retainAll() when filtering a filtered
      // collection.

      return filter((SortedSet<E>) unfiltered, predicate);
    }
    if (unfiltered instanceof FilteredSet) {
      // Support clear(), removeAll(), and retainAll() when filtering a filtered
      // collection.
      FilteredSet<E> filtered = (FilteredSet<E>) unfiltered;
      Predicate<E> combinedPredicate = Predicates.and(filtered.predicate, predicate);
      return new FilteredSet<>((Set<E>) filtered.unfiltered, combinedPredicate);
    }

   *
   * <p><b>{@code Stream} equivalent:</b> {@link java.util.stream.Stream#filter Stream.filter}.
   */
  public static <E extends @Nullable Object> Collection<E> filter(
      Collection<E> unfiltered, Predicate<? super E> predicate) {
    if (unfiltered instanceof FilteredCollection) {
      // Support clear(), removeAll(), and retainAll() when filtering a filtered
      // collection.

        }
    }

    // Test property filter returning null simulation
    @Test
    public void test_get_filterReturnsNull() {
        // The filter.null property is configured to simulate null filter behavior
        try {
            fessConfig.get("filter.null");
            fail("Should throw exception when property is not found");

        assertFalse(iterator.hasNext(), "Should not have more elements");

        // Verify filter was called for each element
        verify(mockFilter, times(2)).accept(any(SmbResource.class));
    }

    /**
     * Test iterator with filter that rejects all elements.
     */
    @Test
    void testIteratorWithFilterRejectingAll() throws CIFSException {
        // Given

# Dateien im Request { #request-files }

Sie können Dateien, die vom Client hochgeladen werden, mithilfe von `File` definieren.

/// info | Info

Um hochgeladene Dateien zu empfangen, installieren Sie zuerst [`python-multipart`](https://github.com/Kludex/python-multipart).

Stellen Sie sicher, dass Sie eine [virtuelle Umgebung](../virtual-environments.md) erstellen, sie aktivieren und dann das Paket installieren, zum Beispiel:

```console

# 정적 파일 { #static-files }

`StaticFiles`를 사용하면 디렉터리에서 정적 파일을 자동으로 제공할 수 있습니다.

## `StaticFiles` 사용 { #use-staticfiles }

* `StaticFiles`를 임포트합니다.
* 특정 경로에 `StaticFiles()` 인스턴스를 "마운트"합니다.

{* ../../docs_src/static_files/tutorial001_py310.py hl[2,6] *}

/// note | 기술 세부사항

`from starlette.staticfiles import StaticFiles`를 사용할 수도 있습니다.

# Запит файлів { #request-files }

Ви можете визначити файли, які будуть завантажуватися клієнтом, використовуючи `File`.

/// info | Інформація

Щоб отримувати завантажені файли, спочатку встановіть [`python-multipart`](https://github.com/Kludex/python-multipart).

Переконайтеся, що ви створили [віртуальне середовище](../virtual-environments.md), активували його, а потім встановили його, наприклад:

```console
$ pip install python-multipart
```