class PackageGraph implements ProgressCheck {

    @Override
    public void identifyPackage(final PackageId packageId, final File file) {
        if (packageId != null) {
            identified.add(packageId);
            // set parent to null in case the package is first extracted as a nested package,
            // then scanned by itself explicitly
            getOrCreateNode(packageId).setParent(null);
        }
    }

}