* exceptions.
   *
   * **The caller must [close][Snapshot.close]** each snapshot returned by [Iterator.next]. Failing
   * to do so leaks open files!
   */
  @Synchronized
  @Throws(IOException::class)
  fun snapshots(): MutableIterator<Snapshot> {
    initialize()
    return object : MutableIterator<Snapshot> {
      /** Iterate a copy of the entries to defend against concurrent modification errors. */

    }

    public void test_getSnapshotActualVersion_valid() {
        String snapshotXml = "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n" + "<metadata>\n" + "  <snapshot>\n"
                + "    <timestamp>20180814.210714</timestamp>\n" + "    <buildNumber>10</buildNumber>\n" + "  </snapshot>\n"
                + "</metadata>";

        PluginHelper testHelper = new PluginHelper() {
            @Override

     */
    void setMetadata(Metadata metadata);

    /**
     * Whether this represents a snapshot.
     *
     * @return if it is a snapshot
     */
    boolean isSnapshot();

    /**
     * Gets the artifact quality this metadata refers to. One of {@link #RELEASE}, {@link #SNAPSHOT} or
     * {@link #RELEASE_OR_SNAPSHOT}.
     *
     * @return The artifact quality this metadata refers to.
     */

    assertThat(buffer1.readUtf8()).isEqualTo(", World")
    val buffer2 = Buffer().writeUtf8("icopter!")
    operator.write(3, buffer2, 7)
    assertThat(buffer2.readUtf8()).isEqualTo("!")
    assertThat<ByteString>(snapshot()).isEqualTo("Helicopter".encodeUtf8())
  }

  @Test
  fun readAndWrite() {
    val operator =
      FileOperator(
        randomAccessFile!!.getChannel(),
      )

    accumulator.addAll(values);
    return accumulator.snapshot();
  }

  /**
   * Returns statistics over a dataset containing the given values.
   *
   * @param values a series of values
   */
  public static Stats of(double... values) {
    StatsAccumulator accumulator = new StatsAccumulator();
    accumulator.addAll(values);
    return accumulator.snapshot();
  }

  /**

        metadata.setVersioning(versioning);
        return metadata;
    }

    protected static Versioning createVersioning(Snapshot snapshot) {
        Versioning versioning = new Versioning();
        versioning.setSnapshot(snapshot);
        return versioning;
    }

    @Override
    public void setMetadata(Metadata metadata) {
        this.metadata = metadata;
    }

<metadata modelVersion="1.1.0">
  <groupId>org.codelibs.fess</groupId>
  <artifactId>fess-ds-atlassian</artifactId>
  <version>12.2.0-SNAPSHOT</version>
  <versioning>
    <snapshot>
      <timestamp>20180814.210714</timestamp>
      <buildNumber>10</buildNumber>
    </snapshot>
    <lastUpdated>20180814210714</lastUpdated>
    <snapshotVersions>
      <snapshotVersion>
        <extension>jar</extension>

 * @since 4.0.0
 */
@Experimental
@Consumer
public interface VersionResolver extends Service {

    /**
     * Resolves an artifact's meta version (if any) to a concrete version.
     * For example, resolves "1.0-SNAPSHOT" to "1.0-20090208.132618-23".
     *
     * @param session The repository session, must not be {@code null}.

  }

  /** Returns an immutable snapshot of the current statistics. */
  public PairedStats snapshot() {
    return new PairedStats(xStats.snapshot(), yStats.snapshot(), sumOfProductsOfDeltas);
  }

  /** Returns the number of pairs in the dataset. */
  public long count() {
    return xStats.count();
  }

  /** Returns an immutable snapshot of the statistics on the {@code x} values alone. */

        assertTrue(range.containsVersion(new DefaultArtifactVersion("1.1-SNAPSHOT")));
        assertTrue(range.containsVersion(new DefaultArtifactVersion("1.2-SNAPSHOT")));

        range = VersionRange.createFromVersionSpec("[1.0-SNAPSHOT,1.2]");

        assertTrue(range.containsVersion(new DefaultArtifactVersion("1.0-SNAPSHOT")));