* only under concurrent modification).
     *
     * To access these fields when you know that they are not null, call the pred() and succ()
     * methods, which perform null checks before returning the fields.
     */
    private @Nullable AvlNode<E> pred;
    private @Nullable AvlNode<E> succ;

    AvlNode(@ParametricNullness E elem, int elemCount) {
      checkArgument(elemCount > 0);

    return executor.submit(
        () -> {
          boolean createSymlink = false;
          while (!Thread.interrupted()) {
            try {
              // trying to switch between a real directory and a symlink (dir -> /a)
              if (Files.deleteIfExists(file)) {
                if (createSymlink) {
                  Files.createSymbolicLink(file, target);

            case 4:
                this.state = 6;
                throw new TransportException("Connection in error", this.te);
            case 5:
            case 6:
                log.debug("Trying to connect a disconnected transport");
                return false;
            default:
                final TransportException tex = new TransportException("Invalid state: " + st);
                throw tex;

2. **Update client applications** to use Fess's JSON Search API (see [API Reference](#api-reference) section)
3. **Gradually migrate** from GSA query format to Fess's native API

**Alternative Approach**: Instead of relying on GSA API compatibility, we recommend migrating client applications to use Fess's modern JSON API (`/api/v1/documents`), which provides more features and better performance.

---

    return new SlicedByteSource(offset, length);
  }

  /**
   * Returns whether the source has zero bytes. The default implementation first checks {@link
   * #sizeIfKnown}, returning true if it's known to be zero and false if it's known to be non-zero.
   * If the size is not known, it falls back to opening a stream and checking for EOF.
   *

   * #intersection(Multiset, Multiset) intersection} {@code (multisetToModify, multisetToRetain)},
   * but mutates {@code multisetToModify} instead of returning a view.
   *
   * <p>In contrast, {@code multisetToModify.retainAll(multisetToRetain)} keeps all occurrences of
   * elements that appear at all in {@code multisetToRetain}, and deletes all occurrences of all

   * #intersection(Multiset, Multiset) intersection} {@code (multisetToModify, multisetToRetain)},
   * but mutates {@code multisetToModify} instead of returning a view.
   *
   * <p>In contrast, {@code multisetToModify.retainAll(multisetToRetain)} keeps all occurrences of
   * elements that appear at all in {@code multisetToRetain}, and deletes all occurrences of all

                   pass -XepCompilingTestOnlyCode, and that argument needs to
                   be passed as part of the same <arg> as -Xplugin:ErrorProne,
                   and I gave up trying to figure out how to do that for test
                   compilation only. -->
              <arg>-Xplugin:ErrorProne -Xep:NullArgumentForNonNullParameter:OFF -Xep:Java8ApiChecker:ERROR</arg>

        @Override
        public int getResponseCode() {
            return 500;
        }

        @Override
        public InputStream getErrorStream() {
            return null; // Simulates server returning no error body
        }

        @Override
        public String getContentEncoding() {
            return null;
        }

        @Override

    final void addDedupedElement(E e) {
      ensureCapacity(distinct + 1);
      dedupedElements[distinct++] = e;
    }

    /**
     * Adds e to this SetBuilderImpl, returning the updated result. Only use the returned
     * SetBuilderImpl, since we may switch implementations if e.g. hash flooding is detected.
     */
    abstract SetBuilderImpl<E> add(E e);