<buildNumber>2</buildNumber>
    </snapshot>
    <lastUpdated>20130404093657</lastUpdated>
    <snapshotVersions>
      <snapshotVersion>
        <extension>pom</extension>
        <value>0.4.0-20130404.090532-2</value>
        <updated>20130404090532</updated>
      </snapshotVersion>
      <snapshotVersion>
        <extension>jar</extension>
        <value>0.4.0-20130404.093655-3</value>

    </snapshot>
    <lastUpdated>20120809112920</lastUpdated>
    <snapshotVersions>
      <snapshotVersion>
        <classifier>classifierA</classifier>
        <extension>jar</extension>
        <value>07.20.3-20120809.112124-88</value>
        <updated>20120809112124</updated>
      </snapshotVersion>
      <snapshotVersion>
        <classifier>classifierB</classifier>
        <extension>jar</extension>

    }

    private static SnapshotVersion addSnapshotVersion(
            Versioning versioning, String extension, Date timestamp, String version, int buildNumber) {
        Snapshot snapshot = new Snapshot();
        snapshot.setBuildNumber(buildNumber);
        snapshot.setTimestamp(formatDate(timestamp, true));

        SnapshotVersion sv = new SnapshotVersion();
        sv.setExtension(extension);

       <<<versioning>>> element that gives data about snapshot (<<<snapshot>>>, <<<lastUpdated>>> and <<<snapshotVersions>>> list). Notice that a
       release artifact directory is not expected to provide metadata.

 []

 The following are generated from this model:

        String lastUpdated = metadata.getVersioning().getLastUpdated();

        Map<String, SnapshotVersion> versions = new LinkedHashMap<>();

        for (Artifact artifact : artifacts) {
            SnapshotVersion sv = new SnapshotVersion();
            sv.setClassifier(artifact.getClassifier());
            sv.setExtension(artifact.getExtension());

                version = version.substring(0, version.length() - SNAPSHOT.length()) + qualifier;
            }

            SnapshotVersion sv = new SnapshotVersion();
            sv.setClassifier(artifact.getClassifier());
            sv.setExtension(artifact.getExtension());
            sv.setVersion(version);
            sv.setUpdated(lastUpdated);

import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Objects;

import org.apache.maven.artifact.repository.metadata.Snapshot;
import org.apache.maven.artifact.repository.metadata.SnapshotVersion;
import org.apache.maven.artifact.repository.metadata.Versioning;
import org.apache.maven.metadata.v4.MetadataStaxReader;
import org.eclipse.aether.RepositoryCache;
import org.eclipse.aether.RepositoryEvent;