public List<ArtifactVersion> getAvailableVersions() {
        return artifact.getAvailableVersions();
    }

    /** {@inheritDoc} */
    public void setAvailableVersions(List<ArtifactVersion> versions) {
        artifact.setAvailableVersions(versions);
    }

    /** {@inheritDoc} */
    public boolean isOptional() {
        return artifact.isOptional();
    }

    /** {@inheritDoc} */

        clone.setRelease(artifact.isRelease());
        clone.setResolvedVersion(artifact.getVersion());
        clone.setResolved(artifact.isResolved());
        clone.setFile(artifact.getFile());

        clone.setAvailableVersions(copyList(artifact.getAvailableVersions()));
        if (artifact.getVersion() != null) {
            clone.setBaseVersion(artifact.getBaseVersion());
        }

    void setArtifactHandler(ArtifactHandler handler);

    boolean isRelease();

    void setRelease(boolean release);

    List<ArtifactVersion> getAvailableVersions();

    void setAvailableVersions(List<ArtifactVersion> versions);

    boolean isOptional();

    void setOptional(boolean optional);

    ArtifactVersion getSelectedVersion() throws OverConstrainedVersionException;

    }

    public List<ArtifactVersion> getAvailableVersions() {
        return parent.getAvailableVersions();
    }

    public void setAvailableVersions(List<ArtifactVersion> availableVersions) {
        throw new UnsupportedOperationException("Cannot change the version information for an attached artifact."
                + " It is derived from the main artifact.");
    }