ArtifactRepositoryPolicy snapshots,
            ArtifactRepositoryPolicy releases) {
        if (snapshots == null) {
            snapshots = new ArtifactRepositoryPolicy();
        }

        if (releases == null) {
            releases = new ArtifactRepositoryPolicy();
        }

        if (globalUpdatePolicy != null) {
            snapshots.setUpdatePolicy(globalUpdatePolicy);

    public ArtifactRepositoryLayout getLayout() {
        return layout;
    }

    public void setSnapshotUpdatePolicy(ArtifactRepositoryPolicy snapshots) {
        this.snapshots = snapshots;
    }

    public ArtifactRepositoryPolicy getSnapshots() {
        return snapshots;
    }

    public void setReleaseUpdatePolicy(ArtifactRepositoryPolicy releases) {
        this.releases = releases;
    }

        if (snapshots == null) {
            snapshots = new ArtifactRepositoryPolicy(
                    true,
                    ArtifactRepositoryPolicy.UPDATE_POLICY_ALWAYS,
                    ArtifactRepositoryPolicy.CHECKSUM_POLICY_IGNORE);
        }

        this.snapshots = snapshots;

        if (releases == null) {
            releases = new ArtifactRepositoryPolicy(
                    true,

    private final Map<Object, LocalSnapshotMetadata> snapshots;

    private final Date timestamp;

    LocalSnapshotMetadataGenerator(RepositorySystemSession session, InstallRequest request) {
        timestamp = (Date) ConfigUtils.getObject(session, new Date(), "maven.startTime");

        snapshots = new LinkedHashMap<>();
    }

    @Override

                RemoteSnapshotMetadata snapshotMetadata = snapshots.get(key);
                if (snapshotMetadata == null) {
                    snapshotMetadata = new RemoteSnapshotMetadata(artifact, timestamp, buildNumber);
                    snapshots.put(key, snapshotMetadata);
                }
                snapshotMetadata.bind(artifact);
            }
        }

        return snapshots.values();
    }

    @Override

            String id,
            String url,
            String layoutId,
            ArtifactRepositoryPolicy snapshots,
            ArtifactRepositoryPolicy releases)
            throws UnknownRepositoryLayoutException {
        return injectSession(factory.createArtifactRepository(id, url, layoutId, snapshots, releases), true);
    }

    public ArtifactRepository createArtifactRepository(
            String id,

class DefaultMirrorSelectorTest {
    @Test
    void testMirrorWithMirrorOfPatternContainingANegationIsNotSelected() {
        ArtifactRepository repository = new DefaultArtifactRepository("snapshots.repo", "http://whatever", null);
        String pattern = "external:*, !snapshots.repo";
        assertFalse(DefaultMirrorSelector.matchPattern(repository, pattern));
    }

  <pluginRepositories>
    <pluginRepository>
      <releases>
        <enabled>false</enabled>
      </releases>
      <snapshots>
        <enabled>true</enabled>
      </snapshots>
      <id>apache.snapshots</id>
      <url>https://repository.apache.org/snapshots/</url>
    </pluginRepository>
  </pluginRepositories>

  <build>
    <finalName>${distributionFileName}</finalName>
    <plugins>

            String layoutId,
            ArtifactRepositoryPolicy snapshots,
            ArtifactRepositoryPolicy releases)
            throws UnknownRepositoryLayoutException;

    ArtifactRepository createArtifactRepository(
            String id,
            String url,
            ArtifactRepositoryLayout repositoryLayout,
            ArtifactRepositoryPolicy snapshots,
            ArtifactRepositoryPolicy releases);

            String id,
            String url,
            ArtifactRepositoryLayout repositoryLayout,
            ArtifactRepositoryPolicy snapshots,
            ArtifactRepositoryPolicy releases) {
        if (snapshots == null) {
            snapshots = new ArtifactRepositoryPolicy();
        }

        if (releases == null) {
            releases = new ArtifactRepositoryPolicy();
        }