*       Objects.equal}{@code (a, b)} implies that {@code predicate.apply(a) ==
   *       predicate.apply(b))}.
   * </ul>
   *
   * @throws NullPointerException if {@code input} is null and this predicate does not accept null
   *     arguments
   */
  boolean apply(@ParametricNullness T input);

  /**
   * Indicates whether another object is equal to this predicate.

    // Assert that escapers throw null pointer exceptions.
    try {
      escaper.escape((String) null);
      Assert.fail("exception not thrown when escaping a null string");
    } catch (NullPointerException e) {
      // pass
    }
  }

  /**
   * Asserts that an escaper escapes the given character into the expected string.
   *
   * @param escaper the non-null escaper to test

 */
@SuppressWarnings("rawtypes") // maybe avoidable if we rework the whole package?
@GwtCompatible
public enum CollectionFeature implements Feature<Collection> {
  /**
   * The collection must not throw {@code NullPointerException} on calls such as {@code
   * contains(null)} or {@code remove(null)}, but instead must return a simple {@code false}.
   */
  ALLOWS_NULL_QUERIES,
  ALLOWS_NULL_VALUES(ALLOWS_NULL_QUERIES),

  /**

    @DisplayName("writeParametersWireFormat throws on null path")
    void testNullPath() {
        Trans2GetDfsReferral cmd = new Trans2GetDfsReferral(null);
        byte[] buffer = new byte[10];
        assertThrows(NullPointerException.class, () -> cmd.writeParametersWireFormat(buffer, 0));
    }

    @Nested
    @DisplayName("read methods are no‑ops")
    class ReadMethods {

        assertNotNull(result);
        assertEquals("", result);
    }

    @Test
    @DisplayName("Should handle null byte array")
    void testToHexStringNull() {
        // When/Then
        assertThrows(NullPointerException.class, () -> {
            Hexdump.toHexString(null);
        });
    }

    @Test
    @DisplayName("Should convert byte array to hex string with offset and length")
    void testHexdumpWithOffset() {

        .build()
    assertThat(headers.toString()).isEqualTo("header1: valué1\n")
  }

  // Fails on JS, ClassCastException: Illegal cast
  @Test fun ofMapThrowsOnNull() {
    assertFailsWith<NullPointerException> {
      (mapOf("User-Agent" to null) as Map<String, String>).toHeaders()
    }
  }

  @Test fun toMultimapGroupsHeaders() {
    val headers =
      Headers.headersOf(
        "cache-control",

  }

  @CollectionSize.Require(absent = ZERO)
  @ListFeature.Require(SUPPORTS_SET)
  @CollectionFeature.Require(absent = ALLOWS_NULL_VALUES)
  public void testSet_nullUnsupported() {
    assertThrows(NullPointerException.class, () -> getList().set(aValidIndex(), null));
    expectUnchanged();
  }

  private int aValidIndex() {
    return getList().size() / 2;
  }

  /**

    }
    expectUnchanged();
  }

  @MapFeature.Require(value = SUPPORTS_PUT, absent = ALLOWS_NULL_KEYS)
  public void testComputeIfAbsent_nullKeyUnsupported() {
    assertThrows(
        NullPointerException.class,
        () ->
            getMap()
                .computeIfAbsent(
                    null,
                    k -> {
                      assertNull(k);
                      return v3();

  @MapFeature.Require(value = SUPPORTS_PUT, absent = ALLOWS_NULL_VALUES)
  public void testAddNullValueUnsupported() {
    Collection<V> result = multimap().asMap().get(k0());
    assertThrows(NullPointerException.class, () -> result.add(null));
  }

  @CollectionSize.Require(absent = ZERO)
  @MapFeature.Require(SUPPORTS_PUT)
  public void testPropagatesAddToMultimap() {

   * set is serializable.
   *
   * @param elements the elements that the set should contain
   * @return a new thread-safe set containing those elements (minus duplicates)
   * @throws NullPointerException if {@code elements} or any of its contents is null
   * @since 15.0
   */
  public static <E> Set<E> newConcurrentHashSet(Iterable<? extends E> elements) {
    Set<E> set = newConcurrentHashSet();