private @Nullable String getCompilerLevel(String level) {
    List<Element> configs = getCompilerConfigs();
    if (configs.size() == 1) return getCompilerLevel(level, configs.get(0));

    return configs.stream()
      .map(element -> MavenJDOMUtil.findChildValueByPath(element, level))
      .filter(Objects::nonNull)
      .map(propertyValue -> LanguageLevel.parse(propertyValue))
      .map(languageLevel -> languageLevel == null ? LanguageLevel.HIGHEST : languageLevel)
      .max(Comparator.naturalOrder())
      .map(l -> l.toJavaVersion().toFeatureString())
      .orElseGet(() -> myState.myProperties.getProperty("maven.compiler." + level));
  }
private @Nullable String getCompilerLevel(String level)