* the elem field without a null check by calling getElement().
     */
    private final @Nullable E elem;

    // elemCount is 0 iff this node has been deleted.
    private int elemCount;

    private int distinctElements;
    private long totalCount;
    private int height;
    private @Nullable AvlNode<E> left;
    private @Nullable AvlNode<E> right;
    /*

    }

    @NotThreadSafe
    class ArtifactFactoryRequestBuilder {
        private Session session;
        private RequestTrace trace;
        private String groupId;
        private String artifactId;
        private String version;
        private String classifier;
        private String extension;
        private String type;

        ArtifactFactoryRequestBuilder() {}

    private SecureKeyManager keyManager;
    private String sessionId;
    private volatile boolean closed = false;

    // Store session key and preauth hash for key rotation
    private byte[] sessionKey;
    private byte[] preauthIntegrityHash;
    private int rotationCount = 0;

    // Key rotation tracking - use atomic for lock-free operations
    private final AtomicLong bytesEncrypted = new AtomicLong(0);

    /** Total number of records available */
    private int allRecordCount;

    /** Total number of pages available */
    private int allPageCount;

    /** Flag indicating if previous page exists */
    private boolean existPrePage;

    /** Flag indicating if next page exists */
    private boolean existNextPage;

    /** List of page numbers for pagination display */
    private List<Integer> pageNumberList;

    /**
     * Total number of records.
     */
    private int allRecordCount;

    /**
     * Total number of pages.
     */
    private int allPageCount;

    /**
     * Flag indicating whether a previous page exists.
     */
    private boolean existPrePage;

    /**
     * Flag indicating whether a next page exists.
     */
    private boolean existNextPage;

    /**

    private int allPageCount;

    /** Whether there is a previous page available */
    private boolean existPrePage;

    /** Whether there is a next page available */
    private boolean existNextPage;

    /** List of page numbers for navigation */
    private List<Integer> pageNumberList;

    /** Number of records per page */
    private int pageSize;

    /** Current page number */
    private int currentPageNumber;

@Timeout(30)
open class TrailersTest {
  private val fileSystem = FakeFileSystem()

  @JvmField
  @RegisterExtension
  val platform = PlatformRule()

  @RegisterExtension
  val clientTestRule = OkHttpClientTestRule()

  @StartStop
  private val server = MockWebServer()

  private var client =
    clientTestRule
      .newClientBuilder()

    // was some asymmetry so that the initial v0 and v1 differ from v2 and v3.
    private long v0 = 0x736f6d6570736575L;
    private long v1 = 0x646f72616e646f6dL;
    private long v2 = 0x6c7967656e657261L;
    private long v3 = 0x7465646279746573L;

    // The number of bytes in the input.
    private long b = 0;

    // The final 64-bit chunk includes the last 0 through 7 bytes of m followed by null bytes

    @NotThreadSafe
    class ArtifactFactoryRequestBuilder {
        private Session session;
        private RequestTrace trace;
        private String groupId;
        private String artifactId;
        private String version;
        private String classifier;
        private String extension;
        private String type;
        private String coordinateString;

        ArtifactFactoryRequestBuilder() {}

                && matches(artifact.getClassifier(), a.getClassifier());
    }

    private static class Relocation {
        private final Predicate<Artifact> predicate;
        private final boolean global;
        private final Artifact source;
        private final Artifact target;

        private Relocation(boolean global, Artifact source, Artifact target) {
            this.predicate = artifactPredicate(source);