*
   * @since 8.0
   */
  public static final byte DLE = 16;

  /**
   * Device Control 1. Characters for the control of ancillary devices associated with data
   * processing or telecommunication systems, more especially switching devices "on" or "off." (If a
   * single "stop" control is required to interrupt or turn off ancillary devices, DC4 is the
   * preferred assignment.)
   *
   * @since 8.0
   */

   *
   * @since 8.0
   */
  public static final byte DLE = 16;

  /**
   * Device Control 1. Characters for the control of ancillary devices associated with data
   * processing or telecommunication systems, more especially switching devices "on" or "off." (If a
   * single "stop" control is required to interrupt or turn off ancillary devices, DC4 is the
   * preferred assignment.)
   *
   * @since 8.0
   */

 * behavior of the stopwatch.
 *
 * <p><b>Note:</b> This class is not thread-safe.
 *
 * <p><b>Warning for Android users:</b> a stopwatch with default behavior may not continue to keep
 * time while the device is asleep. Instead, create one like this:
 *
 * <pre>{@code
 * Stopwatch.createStarted(
 *      new Ticker() {
 *        public long read() {

 * behavior of the stopwatch.
 *
 * <p><b>Note:</b> This class is not thread-safe.
 *
 * <p><b>Warning for Android users:</b> a stopwatch with default behavior may not continue to keep
 * time while the device is asleep. Instead, create one like this:
 *
 * <pre>{@code
 * Stopwatch.createStarted(
 *      new Ticker() {
 *        public long read() {

   * href="https://iabtechlab.com/wp-content/uploads/2019/06/VAST_4.2_final_june26.pdf">{@code
   * X-Device-IP}</a> header field name. Header used for VAST requests to provide the IP address of
   * the device on whose behalf the request is being made.
   *
   * @since 31.0
   */
  public static final String X_DEVICE_IP = "X-Device-IP";
  /**
   * The HTTP <a

     * a given entry might not include null. The right fix for the header problems is probably to
     * define a separate MultimapLink interface with a separate "header" implementation, which
     * hopefully could avoid implementing Entry or ValueSetLink at all. (But note that that approach
     * requires us to define extra classes -- unfortunate under Android.) *Then* we could consider

  }

  private long link(int i) {
    return requireLinks()[i];
  }

  private void setLink(int i, long value) {
    requireLinks()[i] = value;
  }

  /*
   * We don't define getPredecessor+getSuccessor and setPredecessor+setSuccessor here because
   * they're defined above -- including logic to add and subtract 1 to map between the values stored

   */

  private int[] requirePredecessors() {
    return requireNonNull(predecessor);
  }

  private int[] requireSuccessors() {
    return requireNonNull(successor);
  }

  /*
   * We don't define getPredecessor+getSuccessor and setPredecessor+setSuccessor here because
   * they're defined above -- including logic to add and subtract 1 to map between the values stored

   * <p>On the other hand, if for example we are resolving {@code List<A extends B>} to {@code
   * List<A extends String>}, we need to compare that {@code <A extends B>} is unequal to {@code <A
   * extends String>} in order to decide to use the transformed type instead of the original type.
   */
  static final class TypeVariableKey {
    private final TypeVariable<?> var;

    TypeVariableKey(TypeVariable<?> var) {

  }

  private static <T extends @Nullable Object> void successor(
      AvlNode<T> a, AvlNode<T> b, AvlNode<T> c) {
    successor(a, b);
    successor(b, c);
  }

  /*
   * TODO(jlevy): Decide whether entrySet() should return entries with an equals() method that
   * calls the comparator to compare the two keys. If that change is made,