* otherwise, returns {@code defaultValue}.
   *
   * <p>In an undirected graph, this is equal to {@code edgeValueOrDefault(nodeV, nodeU,
   * defaultValue)}.
   *
   * @throws IllegalArgumentException if {@code nodeU} or {@code nodeV} is not an element of this
   *     graph
   */
  @CheckForNull
  V edgeValueOrDefault(N nodeU, N nodeV, @CheckForNull V defaultValue);

  /**

    @SuppressWarnings("unchecked") // Assume all default values are generics safe.
    T defaultValue = (T) defaultValues.getInstance(rawType);
    if (defaultValue != null) {
      return defaultValue;
    }
    @SuppressWarnings("unchecked") // ArbitraryInstances always returns generics-safe dummies.
    T value = (T) ArbitraryInstances.get(rawType);
    if (value != null) {
      return value;
    }

        init();
    }

    private void init() {
        defaultValue = emptySupplier();
        init(defaultValue, noValueSupplier());
    }

    @Override
    public MapSupplier<K, V> getDefaultValue() {
        return defaultValue;
    }

    @Override
    protected MapSupplier<K, V> getDefaultConvention() {
        return noValueSupplier();
    }

   * false} for {@code boolean} and {@code '\0'} for {@code char}. For non-primitive types and
   * {@code void}, {@code null} is returned.
   */
  @SuppressWarnings("unchecked")
  @CheckForNull
  public static <T> T defaultValue(Class<T> type) {
    checkNotNull(type);
    if (type.isPrimitive()) {
      if (type == boolean.class) {
        return (T) Boolean.FALSE;
      } else if (type == char.class) {

    }

    @Override
    public Path getPath() {
        return artifact.getPath();
    }

    @Override
    public String getProperty(String key, String defaultValue) {
        return artifact.getProperty(key, defaultValue);
    }

    @Override
    public Map<String, String> getProperties() {
        return artifact.getProperties();
    }

    public String getMessage() {

   * determined.
   */
  public static <T> @Nullable T get(Class<T> type) {
    T defaultValue = DEFAULTS.getInstance(type);
    if (defaultValue != null) {
      return defaultValue;
    }
    Class<? extends T> implementation = getImplementation(type);
    if (implementation != null) {
      return get(implementation);
    }

   * false} for {@code boolean} and {@code '\0'} for {@code char}. For non-primitive types and
   * {@code void}, {@code null} is returned.
   */
  @SuppressWarnings("unchecked")
  @CheckForNull
  public static <T> T defaultValue(Class<T> type) {
    checkNotNull(type);
    if (type.isPrimitive()) {
      if (type == boolean.class) {
        return (T) Boolean.FALSE;
      } else if (type == char.class) {

    @Override
    public Object get(final Object key) {
        return getProperties().get(key);
    }

    @Override
    public String getProperty(final String key, final String defaultValue) {
        return getProperties().getProperty(key, defaultValue);
    }

    @Override
    public String getProperty(final String key) {
        return getProperties().getProperty(key);
    }

    @Override

    private DocumentUtil() {
    }

    public static <T> T getValue(final Map<String, Object> doc, final String key, final Class<T> clazz, final T defaultValue) {
        final T value = getValue(doc, key, clazz);
        if (value == null) {
            return defaultValue;
        }
        return value;
    }

    @SuppressWarnings("unchecked")

    public V edgeValueOrDefault(N nodeU, N nodeV, @CheckForNull V defaultValue) {
      return delegate().edgeValueOrDefault(nodeV, nodeU, defaultValue); // transpose
    }

    @Override
    @CheckForNull
    public V edgeValueOrDefault(EndpointPair<N> endpoints, @CheckForNull V defaultValue) {
      return delegate().edgeValueOrDefault(transpose(endpoints), defaultValue);
    }
  }