@Override
  public List<JpsPackagingElement> getSubstitution() {
    JpsArtifact artifact = getArtifactReference().resolve();
    if (artifact == null) return Collections.emptyList();
    JpsCompositePackagingElement rootElement = artifact.getRootElement();
    if (rootElement instanceof JpsArtifactRootElement) {
      return new ArrayList<>(rootElement.getChildren());
    }
    else {
      return Collections.singletonList(rootElement);
    }
  }
@Override
  public List<JpsPackagingElement> getSubstitution()