assertSize(3);
    assertThrows(NullPointerException.class, () -> table.put(null, 2, cellValue('d')));
    assertThrows(NullPointerException.class, () -> table.put("cat", null, cellValue('d')));
    if (supportsNullValues()) {
      assertThat(table.put("cat", 2, null)).isNull();
      assertTrue(table.contains("cat", 2));
    } else {
      assertThrows(NullPointerException.class, () -> table.put("cat", 2, null));
    }

              });
      fail("Expected NullPointerException or UnsupportedOperationException");
    } catch (NullPointerException | UnsupportedOperationException expected) {
    }
  }

  public void testMergeNullFunction() {
    try {
      getMap().merge(k0(), v3(), null);
      fail("Expected NullPointerException or UnsupportedOperationException");
    } catch (NullPointerException | UnsupportedOperationException expected) {

  public void testReplace_presentNullValueUnsupported() {
    assertThrows(NullPointerException.class, () -> getMap().replace(k0(), null));
    expectUnchanged();
  }

  @MapFeature.Require(value = SUPPORTS_PUT, absent = ALLOWS_NULL_VALUE_QUERIES)
  public void testReplace_absentNullValueUnsupported() {
    try {
      getMap().replace(k3(), null);
    } catch (NullPointerException tolerated) {
      // permitted not to throw because it would be a no-op

  public void testReplace_presentNullValueUnsupported() {
    assertThrows(NullPointerException.class, () -> getMap().replace(k0(), null));
    expectUnchanged();
  }

  @MapFeature.Require(value = SUPPORTS_PUT, absent = ALLOWS_NULL_VALUE_QUERIES)
  public void testReplace_absentNullValueUnsupported() {
    try {
      getMap().replace(k3(), null);
    } catch (NullPointerException tolerated) {
      // permitted not to throw because it would be a no-op

  }

  public void testOfNullKey() {
    assertThrows(NullPointerException.class, () -> ImmutableMap.of(null, 1));

    assertThrows(NullPointerException.class, () -> ImmutableMap.of("one", 1, null, 2));
  }

  public void testOfNullValue() {
    assertThrows(NullPointerException.class, () -> ImmutableMap.of("one", null));

    assertThrows(NullPointerException.class, () -> ImmutableMap.of("one", 1, "two", null));
  }

        assertTrue(customFilter.accept(file), "Wildcard should be ignored in accept");
    }

    @Test
    public void testAcceptHandlesNullFile() {
        assertThrows(NullPointerException.class, () -> filter.accept(null));
    }

    assertThrows(NullPointerException.class, () -> builder.put(null, 1));
    assertThrows(NullPointerException.class, () -> builder.putAll(null, Arrays.asList(1, 2, 3)));
    assertThrows(NullPointerException.class, () -> builder.putAll(null, 1, 2, 3));
    assertThrows(
        NullPointerException.class, () -> builder.putAll((Multimap<String, Integer>) toPut));
  }

            // Test with concrete implementation - behavior depends on implementation
            // May throw NullPointerException
            try {
                concreteImplementation.append(null);
            } catch (NullPointerException e) {
                // Expected for some implementations
            }
        }
    }

    @Nested

   *
   * @throws NullPointerException if any element is null
   */
  public static <E extends Comparable<? super E>> ImmutableSortedMultiset<E> of(
      E e1, E e2, E e3, E e4) {
    return copyOf(Ordering.natural(), Arrays.asList(e1, e2, e3, e4));
  }

  /**
   * Returns an immutable sorted multiset containing the given elements sorted by their natural
   * ordering.
   *
   * @throws NullPointerException if any element is null

        if (element == null) {
          throw new NullPointerException();
        }
      }
    }
  }

  @Override
  public int size() {
    return contents.length;
  }

  @Override
  public boolean contains(@Nullable Object object) {
    if (!allowNulls) {
      // behave badly
      if (object == null) {
        throw new NullPointerException();
      }
    }