* @return the metadata, or <code>null</code> if none loaded
     */
    Metadata getMetadata();

    /**
     * Set the metadata contents.
     *
     * @param metadata the metadata
     */
    void setMetadata(Metadata metadata);

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

    /**

        Versioning versioning = new Versioning();
        versioning.setSnapshot(snapshot);
        return versioning;
    }

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

    @Override
    public Metadata getMetadata() {
        return metadata;
    }

    @Override