void (@NotNull Element state) { myIgnoredUnknownFeatures.clear(); for (Element element : state.getChildren()) { String featureType = element.getAttributeValue(FEATURE_ID); if (featureType == null) continue; String implementationName = element.getAttributeValue(IMPLEMENTATION_NAME); if (implementationName == null) continue; myIgnoredUnknownFeatures.add(new UnknownFeature(featureType, implementationName)); } }