Ele foi uma das primeiras implementações de um framework usando Python _type hints_ para declarar parâmetros e requisições que eu nunca vi (antes no NestJS e Molten). Eu encontrei ele mais ou menos na mesma época que o Hug. Mas o APIStar utilizava o padrão OpenAPI.

Ele tinha validação de dados automática, serialização de dados e geração de _schema_ OpenAPI baseado nos mesmos _type hints_ em vários locais.

            ListTestSuiteBuilder.using(new IntsAsListTailSubListGenerator())
                .named("Ints.asList, tail subList"),
            ListTestSuiteBuilder.using(new IntsAsListMiddleSubListGenerator())
                .named("Ints.asList, middle subList"));

    TestSuite suite = new TestSuite();
    for (ListTestSuiteBuilder<Integer> builder : builders) {
      suite.addTest(
          builder

import com.google.common.primitives.Ints;
import org.jspecify.annotations.Nullable;

/**
 * Static methods for implementing hash-based collections.
 *
 * @author Kevin Bourrillion
 * @author Jesse Wilson
 * @author Austin Appleby
 */
@GwtCompatible
final class Hashing {
  private Hashing() {}

  /*
   * These should be ints, but we need to use longs to force GWT to do the multiplications with

package org.apache.maven.building;

/**
 * Describes a problem that was encountered during settings building. A problem can either be an exception that was
 * thrown or a simple string message. In addition, a problem carries a hint about its source, e.g. the settings file
 * that exhibits the problem.
 *
 * @deprecated since 4.0.0, use {@link org.apache.maven.api.services} instead
 */
@Deprecated(since = "4.0.0")

  private static final int[] nonzero = new int[ARRAY_SIZE];
  private static final int[] ints = new int[ARRAY_SIZE];

  @BeforeExperiment
  void setUp() {
    for (int i = 0; i < ARRAY_SIZE; i++) {
      positive[i] = randomPositiveBigInteger(Integer.SIZE - 2).intValue();
      nonzero[i] = randomNonZeroBigInteger(Integer.SIZE - 2).intValue();
      ints[i] = RANDOM_SOURCE.nextInt();
    }
  }

    void constructorWithNullAndx() {
        SmbComLogoffAndX msg = new SmbComLogoffAndX(null);
        assertNotNull(msg, "Message must not be null after construction");
    }

    @ParameterizedTest
    @ValueSource(ints = { 0, 1, 5, -1, 10 })
    @DisplayName("writeParameterWordsWireFormat always returns 0")
    void writeParameterWordsWireFormatReturnsZero(int index) {
        SmbComLogoffAndX msg = new SmbComLogoffAndX(null);

            notifyInfo.decode(buffer, 0, buffer.length);
        }, "Non aligned nextEntryOffset");
    }

    @ParameterizedTest
    @DisplayName("Test decode with various action values")
    @ValueSource(ints = { FileNotifyInformation.FILE_ACTION_ADDED, FileNotifyInformation.FILE_ACTION_REMOVED,
            FileNotifyInformation.FILE_ACTION_MODIFIED, FileNotifyInformation.FILE_ACTION_RENAMED_OLD_NAME,

                scrollId = response.getScrollId();
                final SearchHit[] hits = response.getHits().getHits();
                if (scrollId == null || hits.length == 0) {
                    SuggestUtil.deleteScrollContext(client, scrollId);
                    isFinished.set(true);
                }

                for (final SearchHit hit : hits) {
                    final Map<String, Object> source = hit.getSourceAsMap();

    }

    /**
     * Validate that the constructor masks the supplied value to its
     * lowest 8 bits (NdrShort incorrectly masks to 8 bits even though it's a short).
     */
    @ParameterizedTest
    @ValueSource(ints = { 0, 1, 255, -1, 256, 65535 })
    void constructorMasksValue(int input) {
        NdrShort ns = new NdrShort(input);
        // NdrShort masks to 0xFF (8 bits) in its constructor
        int expected = input & 0xFF;

    }

    protected SearchHits getSearchHits(final SearchResponse response) {
        SearchHits hits = response.getHits();
        if (hits == null) {
            throw new IllegalBehaviorStateException("hits is null: " + response);
        }
        return hits;
    }

    public static class BulkList<E, B> implements List<E> {

        private final List<E> parent;