initMapWithNullValue();

    // putIfAbsent should replace the null value with the new value
    assertNull(
        "putIfAbsent(existingKeyWithNullValue, value) should return null",
        getMap().putIfAbsent(getKeyForNullValue(), v3()));
    assertEquals("Map should now contain the new value", v3(), getMap().get(getKeyForNullValue()));
  }

     * information to search engines and may not correlate exactly to how often
     * they crawl the page. Valid values are:
     * <ul>
     * <li>always</li>
     * <li>hourly</li>
     * <li>daily</li>
     * <li>weekly</li>
     * <li>monthly</li>
     * <li>yearly</li>
     * <li>never</li>
     * </ul>

  abstract void setCountCheckReturnValue(E element, int count);

  /**
   * Call the {@code setCount()} method under test, but do not check its return value. Callers
   * should use this method over {@link #setCountCheckReturnValue(Object, int)} when they expect
   * {@code setCount()} to throw an exception, as checking the return value could produce an

     */
    public static StreamOf<String> split(final String value, final String regex) {
        return stream(value == null ? null : value.split(regex));
    }

    /**
     * Creates a stream of map entries from the given map.
     *
     * @param <K> the type of keys in the map
     * @param <V> the type of values in the map

  @MapFeature.Require(SUPPORTS_REMOVE)
  /*
   * We are comparing Multimaps of the same type, so as long as they have value collections that
   * implement equals() (as with ListMultimap or SetMultimap, as opposed to a QueueMultimap or
   * something), our equality check is value-based.
   */
  @SuppressWarnings("UndefinedEquals")
  public void testRetainAllPropagatesToMultimap() {

    expectUnchanged();
  }

  @MapFeature.Require(value = SUPPORTS_PUT, absent = ALLOWS_NULL_VALUES)
  @CollectionSize.Require(absent = ZERO)
  public void testReplaceEntry_presentNullValueUnsupported() {
    assertThrows(NullPointerException.class, () -> getMap().replace(k0(), v0(), null));
    expectUnchanged();
  }

  @MapFeature.Require(value = SUPPORTS_PUT, absent = ALLOWS_NULL_VALUE_QUERIES)

 * Helper type to implement rounding {@code X} to a representable {@code double} value according to
 * a {@link RoundingMode}.
 */
@GwtIncompatible
abstract class ToDoubleRounder<X extends Number & Comparable<X>> {
  /**
   * Returns x rounded to either the greatest double less than or equal to the precise value of x,
   * or the least double greater than or equal to the precise value of x.
   */
  abstract double roundToDoubleArbitrarily(X x);

    }

    protected void assertObjectNotNull(String variableName, Object value) {
        if (variableName == null) {
            String msg = "The value should not be null: variableName=null value=" + value;
            throw new IllegalArgumentException(msg);
        }
        if (value == null) {
            String msg = "The value should not be null: variableName=" + variableName;

    }

    protected void assertObjectNotNull(String variableName, Object value) {
        if (variableName == null) {
            String msg = "The value should not be null: variableName=null value=" + value;
            throw new IllegalArgumentException(msg);
        }
        if (value == null) {
            String msg = "The value should not be null: variableName=" + variableName;

  private static final class JavaNioCreator extends TempFileCreator {
    @Override
    File createTempDir() {
      try {
        return java.nio.file.Files.createTempDirectory(
                Paths.get(JAVA_IO_TMPDIR.value()), /* prefix= */ null, directoryPermissions.get())
            .toFile();
      } catch (IOException e) {
        throw new IllegalStateException("Failed to create directory", e);
      }
    }

    @Override