propertyNames.mapNotNull { propertyName ->
        stringPropertyOrNull(propertyName)?.let { propertyValue ->
            propertyName to propertyValue
        }
    }.toMap()

/**
 * Creates a [Provider] that returns `true` when this [Provider] has a value
 * and `false` otherwise. The returned [Provider] always has a value.
 * @see Provider.isPresent
 */
private

   * @since 14.0
   */
  @SuppressWarnings("nullness") // Unsafe, but we can't do much about it now.
  public final <V> ImmutableMap<@NonNull E, V> toMap(Function<? super E, V> valueFunction) {
    return Maps.toMap((Iterable<@NonNull E>) getDelegate(), valueFunction);
  }

  /**
   * Creates an index {@code ImmutableListMultimap} that contains the results of applying a

                            b.executeAfter(a);
                            c.executeAfter(b);
                            return Stream.of(a, b, c);
                        })
                        .collect(Collectors.toMap(n -> n.name, n -> n));
                // for each phase, make sure children phases are executed between before and after steps
                lifecycle.allPhases().forEach(phase -> phase.phases().forEach(child -> {

                .map(ModelBase::getProperties)
                .flatMap(properties -> properties.entrySet().stream())
                .filter(e -> e.getValue() != null)
                .collect(Collectors.toMap(
                        e -> String.valueOf(e.getKey()), e -> String.valueOf(e.getValue()), (k1, k2) -> k2));
    }

    private String getUserAgent() {
        String version = runtimeInformation.getMavenVersion();

			tagMap := map[string]string{}
			tagStr := info.Metadata[xhttp.AmzObjectTagging]
			if len(tagStr) != 0 {
				t, err := tags.ParseObjectTags(tagStr)
				if err != nil {
					return false
				}
				tagMap = t.ToMap()
			}

			for _, kv := range r.Flags.Filter.Tags {
				for t, v := range tagMap {
					if kv.Match(BatchJobKV{Key: t, Value: v}) {
						return true
					}
				}
			}

    checkNotNull(comparator);
    checkNotNull(keyFunction);
    checkNotNull(valueFunction);
    checkNotNull(mergeFunction);
    return Collectors.collectingAndThen(
        Collectors.toMap(
            keyFunction, valueFunction, mergeFunction, () -> new TreeMap<K, V>(comparator)),
        ImmutableSortedMap::copyOfSorted);
  }

  // unsafe, comparator() returns a comparator on the specified type

   * the collection operation is performed. (This differs from the {@code Collector} returned by
   * {@link java.util.stream.Collectors#toMap(java.util.function.Function,
   * java.util.function.Function) Collectors.toMap(Function, Function)}, which throws an {@code
   * IllegalStateException}.)
   *
   * @since 33.2.0 (available since 21.0 in guava-jre)
   */

   * the collection operation is performed. (This differs from the {@code Collector} returned by
   * {@link java.util.stream.Collectors#toMap(java.util.function.Function,
   * java.util.function.Function) Collectors.toMap(Function, Function)}, which throws an {@code
   * IllegalStateException}.)
   *
   * @since 21.0
   */
  public static <T extends @Nullable Object, K extends Enum<K>, V>

     * @return The converted map.
     */
    protected Map<String, Object> toLowerHyphen(final Map<String, Object> source) {
        return source.entrySet()
                .stream()
                .collect(Collectors.toMap(e -> CaseFormat.UPPER_CAMEL.to(CaseFormat.LOWER_UNDERSCORE, e.getKey()), e -> {
                    final Object value = e.getValue();
                    if (value instanceof Map) {

   *
   * <p>If multiple input elements map to the same row and column, the specified merging function is
   * used to combine the values. Like {@link
   * java.util.stream.Collectors#toMap(java.util.function.Function, java.util.function.Function,
   * BinaryOperator, java.util.function.Supplier)}, this Collector throws a {@code
   * NullPointerException} on null values returned from {@code valueFunction}, and treats nulls