// if the POM didn't exist, retry if any repo is configured to always update
                    boolean snapshot = pomArtifact.isSnapshot();
                    for (ArtifactRepository repository : remoteRepositories) {
                        ArtifactRepositoryPolicy policy =
                                snapshot ? repository.getSnapshots() : repository.getReleases();

    cache.invalidateAll(toInvalidate);
    assertEquals(toInvalidate, invalidated);
  }

  public void testEmptySimpleStats() {
    StatsCounter counter = new SimpleStatsCounter();
    CacheStats stats = counter.snapshot();
    assertEquals(0, stats.requestCount());
    assertEquals(0, stats.hitCount());
    assertEquals(1.0, stats.hitRate());
    assertEquals(0, stats.missCount());
    assertEquals(0.0, stats.missRate());

     */
    @Nonnull
    String getExtension();

    /**
     * Determines whether this artifact uses a snapshot version.
     *
     * @return {@code true} if the artifact is a snapshot, {@code false} otherwise
     * @see org.apache.maven.api.Session#isVersionSnapshot(String)
     */
    boolean isSnapshot();

    /**
     * Shortcut for {@code session.createArtifactCoordinate(artifact)}
     *

        assertVersionOlder("1.0.0-SNAPSHOT", "1.1-SNAPSHOT");
        assertVersionOlder("1.1-SNAPSHOT", "1.2.0-SNAPSHOT");

        // assertVersionOlder( "1.0-alpha-1-SNAPSHOT", "1.0-SNAPSHOT" );
        assertVersionOlder("1.0-alpha-1-SNAPSHOT", "1.0-alpha-2-SNAPSHOT");
        assertVersionOlder("1.0-alpha-1-SNAPSHOT", "1.0-beta-1-SNAPSHOT");

        assertVersionOlder("1.0-beta-1-SNAPSHOT", "1.0-SNAPSHOT-SNAPSHOT");

                    throws Exception {
        Artifact i = createRemoteArtifact("i", "1.0-SNAPSHOT");
        deleteLocalArtifact(i);

        Artifact j = createRemoteArtifact("j", "1.0-SNAPSHOT");
        deleteLocalArtifact(j);

        ArtifactResolutionResult result = artifactResolver.resolveTransitively(

     * 1. 1.2.7 == 1.2.7
     *    1.2.7 > 1.2-SNAPSHOT
     * 2. 1.2-SNAPSHOT == 1.2-snapshot
     * </pre>
     *
     * @param args the version strings to parse and compare. You can pass arbitrary number of version strings and always
     *             two adjacent will be compared.
     */
    // CHECKSTYLE_ON: LineLength
    public static void main(String... args) {

        Snapshot snapshot;
        String lastUpdated;

        if (metadata.getVersioning() == null) {
            DateFormat utcDateFormatter = new SimpleDateFormat(DEFAULT_SNAPSHOT_TIMESTAMP_FORMAT);
            utcDateFormatter.setCalendar(new GregorianCalendar());
            utcDateFormatter.setTimeZone(DEFAULT_SNAPSHOT_TIME_ZONE);

            snapshot = Snapshot.newBuilder()

     */
    @Nonnull
    VersionConstraint parseVersionConstraint(@Nonnull String constraint);

    /**
     * Checks whether a given artifact version is considered a {@code SNAPSHOT} or not.
     */
    boolean isSnapshot(@Nonnull String version);

         * DefaultRepositoryLayout does not correctly describe the layout of a local repository which unlike a remote
         * repository never uses timestamps in the filename of a snapshot artifact. The discrepancy gets notable when a
         * remotely resolved snapshot artifact gets passed into pathOf(). So producing a proper local artifact path
         * using DefaultRepositoryLayout requires us to enforce usage of the artifact's base version. This

    }

    @Override
    public String getVersion() {
        return "";
    }

    @Override
    public Nature getNature() {
        return artifact.isSnapshot() ? Nature.RELEASE_OR_SNAPSHOT : Nature.RELEASE;
    }