@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;
    }

    assertEquals(false, Defaults.defaultValue(boolean.class).booleanValue());
    assertEquals('\0', Defaults.defaultValue(char.class).charValue());
    assertEquals(0, Defaults.defaultValue(byte.class).byteValue());
    assertEquals(0, Defaults.defaultValue(short.class).shortValue());
    assertEquals(0, Defaults.defaultValue(int.class).intValue());
    assertEquals(0, Defaults.defaultValue(long.class).longValue());

    assertEquals(false, Defaults.defaultValue(boolean.class).booleanValue());
    assertEquals('\0', Defaults.defaultValue(char.class).charValue());
    assertEquals(0, Defaults.defaultValue(byte.class).byteValue());
    assertEquals(0, Defaults.defaultValue(short.class).shortValue());
    assertEquals(0, Defaults.defaultValue(int.class).intValue());
    assertEquals(0, Defaults.defaultValue(long.class).longValue());

        FessConfig fessConfig = new FessConfig.SimpleImpl() {
            @Override
            public String getSystemProperty(final String key, final String defaultValue) {
                return systemPropMap.getOrDefault(key, defaultValue);
            }
        };
        ComponentUtil.setFessConfig(fessConfig);
        SystemHelper systemHelper = new SystemHelper() {
            @Override

    return edgeValueOrDefaultInternal(checkNotNull(nodeU), checkNotNull(nodeV), defaultValue);
  }

  @Override
  public @Nullable V edgeValueOrDefault(EndpointPair<N> endpoints, @Nullable V defaultValue) {
    validateEndpoints(endpoints);
    return edgeValueOrDefaultInternal(endpoints.nodeU(), endpoints.nodeV(), defaultValue);
  }

  @Override

   * Returns the first element in {@code iterable} that satisfies the given predicate, or {@code
   * defaultValue} if none found. Note that this can usually be handled more naturally using {@code
   * tryFind(iterable, predicate).or(defaultValue)}.
   *
   * <p><b>{@code Stream} equivalent:</b> {@code
   * stream.filter(predicate).findFirst().orElse(defaultValue)}
   *
   * @since 7.0
   */
  // The signature we really want here is...
  //

        assertNull(dataStoreParams.getAsString("nonExistentKey"));
        assertEquals("defaultValue", dataStoreParams.getAsString("nonExistentKey", "defaultValue"));

        dataStoreParams.put("nullKey", null);
        assertEquals("defaultValue", dataStoreParams.getAsString("nullKey", "defaultValue"));
    }

) {
  /**
   * Returns the charset of this media type, or [defaultValue] if either this media type doesn't
   * specify a charset, or if its charset is unsupported by the current runtime.
   */
  @JvmOverloads
  fun charset(defaultValue: Charset? = null): Charset? {
    val charset = parameter("charset") ?: return defaultValue
    return try {
      Charset.forName(charset)
    } catch (_: IllegalArgumentException) {

            return defaultValue != null ? defaultValue.toString() : StringUtil.EMPTY;
        } catch (final Exception e) {
            return StringUtil.EMPTY;
        }
    }

    private String getDefaultMaxKey() {
        try {
            final Method method = CustomSize.class.getMethod("maxKey");
            final Object defaultValue = method.getDefaultValue();

     *
     * @param key the property key
     * @param defaultValue the default value
     * @return the property value, or the default value if not found
     */
    public static String getProperty(String key, String defaultValue) {
        return System.getProperty(key, defaultValue);
    }

    /**
     * Returns the system environment variable value for the specified key.
     *