Set<Entry<K, V>> entrySet = map.entrySet();
    if (supportsRemove) {
      assertThrows(NullPointerException.class, () -> entrySet.removeAll(null));
    } else {
      try {
        entrySet.removeAll(null);
        fail("Expected UnsupportedOperationException or NullPointerException.");
      } catch (UnsupportedOperationException | NullPointerException e) {
        // Expected.
      }
    }
    assertInvariants(map);
  }

    Set<Entry<K, V>> entrySet = map.entrySet();
    if (supportsRemove) {
      assertThrows(NullPointerException.class, () -> entrySet.removeAll(null));
    } else {
      try {
        entrySet.removeAll(null);
        fail("Expected UnsupportedOperationException or NullPointerException.");
      } catch (UnsupportedOperationException | NullPointerException e) {
        // Expected.
      }
    }
    assertInvariants(map);
  }

   *
   * @throws NullPointerException if the element is null
   */
  public static <E> ImmutableList<E> of(E e1) {
    return new SingletonImmutableList<>(e1);
  }

  /**
   * Returns an immutable list containing the given elements, in order.
   *
   * @throws NullPointerException if any element is null
   */
  public static <E> ImmutableList<E> of(E e1, E e2) {

                "The exception should be either PACDecodingException or NullPointerException.");

        if (exception instanceof PACDecodingException) {
            assertEquals("Malformed kerberos ticket", exception.getMessage(), "PAC exception should indicate malformed ticket.");
        } else if (exception instanceof NullPointerException) {
            // Empty input causes null ASN1 object, which is expected behavior

    /**
     * Ensure encode throws NPE when passed a null buffer.
     */
    @Test
    @DisplayName("Encode with null buffer throws NullPointerException")
    public void testEncodeNullBuffer() throws NdrException {
        NdrHyper hyper = new NdrHyper(5L);
        assertThrows(NullPointerException.class, () -> hyper.encode(null));
    }

    /**
     * Ensure decode throws NPE when passed a null buffer.
     */
    @Test

    assertThrows(NullPointerException.class, () -> builder.add((String) null));
  }

  public void testBuilderAddAllHandlesNullsCorrectly() {
    {
      ImmutableSortedMultiset.Builder<String> builder = ImmutableSortedMultiset.naturalOrder();
      assertThrows(NullPointerException.class, () -> builder.addAll((Collection<String>) null));
    }

    {

    ImmutableList.Builder<String> builder = ImmutableList.builder();
    assertThrows(NullPointerException.class, () -> builder.add((String) null));

    assertThrows(NullPointerException.class, () -> builder.add((String[]) null));

    assertThrows(NullPointerException.class, () -> builder.add("a", null, "b"));
  }

  public void testBuilderAddAllHandlesNullsCorrectly() {
    {

     * Null pointer scenario – calls on a null reference should raise
     * {@link NullPointerException}. This test is defensive; in real code it
     * would likely be handled elsewhere.
     */
    @Test
    @DisplayName("calling getters on null reference throws NPE")
    void testNullReference() {
        AllocInfo nullRef = null;
        assertThrows(NullPointerException.class, () -> nullRef.getCapacity());

    @DisplayName("Should handle null input gracefully")
    void testNullInputHandling() {
        // When/Then
        assertThrows(NullPointerException.class, () -> {
            MessageDigest md4 = Crypto.getMD4();
            md4.digest(null);
        });

        assertThrows(NullPointerException.class, () -> {
            MessageDigest md5 = Crypto.getMD5();
            md5.digest(null);
        });
    }

   * fail to insert an element only by throwing an exception.
   *
   * @throws NullPointerException if the specified element is null
   */
  @CanIgnoreReturnValue
  @Override
  public boolean offer(E e) {
    if (e == null) throw new NullPointerException();
    Monitor monitor = this.monitor;
    if (monitor.enterIf(notFull)) {
      try {
        insert(e);