* @return The effective repositories or {@code null} if the input was {@code null}.
     */
    List<ArtifactRepository> getEffectiveRepositories(List<ArtifactRepository> repositories);

    /**
     * Determines the mirror for the specified repository.
     *
     * @param repository The repository to determine the mirror for, must not be {@code null}.

    /**
     *
     * @param model the model, must not be {@code null}
     * @param logger the logger, must not be {@code null}
     */
    protected DefaultToolchain(ToolchainModel model, Logger logger) {
        this.model = model;
        this.logger = logger;
    }

    /**
     *
     * @param model the model, must not be {@code null}
     * @param type the type

            throws UnresolvableModelException {
        File pomFile = null;

        if (modelPool != null) {
            pomFile = modelPool.get(groupId, artifactId, version);
        }

        if (pomFile == null) {
            Artifact pomArtifact = new DefaultArtifact(groupId, artifactId, "", "pom", version);

            try {

import okio.ByteString.Companion.encodeUtf8
import okio.IOException
import okio.Source
import okio.buffer

class ResponseBodyTest {
  @Test
  fun sourceEmpty() {
    val mediaType = if (null == null) null else "any/thing; charset=${null}".toMediaType()
    val body = "".decodeHex().toResponseBody(mediaType)
    val source = body.source()
    assertThat(source.exhausted()).isTrue()
    assertThat(source.readUtf8()).isEqualTo("")
  }

        // Intentionally notNull because Super POM may not contain a modelId
        Objects.requireNonNull(modelId, "modelId cannot null");

        if (activeProfiles != null) {
            this.activePomProfiles.put(modelId, new ArrayList<>(activeProfiles));
        } else {
            this.activePomProfiles.remove(modelId);
        }

        return this;

        this.lookup = requireNonNull(lookup, "lookup cannot be null");
        this.languageRegistry = requireNonNull(languageRegistry, "languageRegistry cannot be null");
        this.usedTypes = new ConcurrentHashMap<>();
        this.manager = requireNonNull(manager, "artifactHandlerManager cannot be null");
    }

    @Override
    public void onEvent(Object event) {

      List<Cell<R, C, V>> cells,
      @Nullable Comparator<? super R> rowComparator,
      @Nullable Comparator<? super C> columnComparator) {
    checkNotNull(cells);
    if (rowComparator != null || columnComparator != null) {
      /*
       * This sorting logic leads to a cellSet() ordering that may not be expected and that isn't
       * documented in the Javadoc. If a row Comparator is provided, cellSet() iterates across the

          public int getCount() {
            Count count = mapEntry.getValue();
            if (count == null || count.get() == 0) {
              Count frequency = backingMap.get(getElement());
              if (frequency != null) {
                return frequency.get();
              }
            }
            return (count == null) ? 0 : count.get();
          }
        };
      }

      @Override

    }

    @Override
    public @Nullable K get(@Nullable Object value) {
      if (value == null || valueTable == null) {
        return null;
      }
      int bucket = Hashing.smear(value.hashCode()) & mask;
      for (ImmutableMapEntry<K, V> entry = valueTable[bucket];
          entry != null;
          entry = entry.getNextInValueBucket()) {
        if (value.equals(entry.getValue())) {

     *
     * @param request The execution request to populate, must not be {@code null}.
     * @param toolchains The toolchains to copy into the execution request, may be {@code null}.
     * @return The populated execution request, never {@code null}.
     * @throws MavenExecutionRequestPopulationException If the execution request could not be populated.
     * @since 3.3.0
     */