{
    if (group == null)
    {
      EAnnotation eAnnotation = getAnnotation(eStructuralFeature, false);
      if (eAnnotation != null)
      {
        eAnnotation.getDetails().remove("group");
      }
    }
    else
    {
      EAnnotation eAnnotation = getAnnotation(eStructuralFeature, true);
      eAnnotation.getDetails().put
        ("group", getQualifiedName(getNamespace(eStructuralFeature.getEContainingClass().getEPackage()), group));
    }
    getExtendedMetaData(eStructuralFeature).setGroup(group);
  }