class MavenSettingsMerger {

    /**
     * @param dominant
     * @param recessive
     * @param recessiveSourceLevel
     */
    public void merge(Settings dominant, Settings recessive, String recessiveSourceLevel) {<FILL_FUNCTION_BODY>}

    /**
     * @param dominant
     * @param recessive
     * @param recessiveSourceLevel
     */
    private static <T extends IdentifiableBase> void shallowMergeById(
            List<T> dominant, List<T> recessive, String recessiveSourceLevel) {
        Map<String, T> dominantById = mapById(dominant);
        final List<T> identifiables = new ArrayList<>(recessive.size());

        for (T identifiable : recessive) {
            if (!dominantById.containsKey(identifiable.getId())) {
                identifiable.setSourceLevel(recessiveSourceLevel);

                identifiables.add(identifiable);
            }
        }

        dominant.addAll(0, identifiables);
    }

    /**
     * @param identifiables
     * @return a map
     */
    private static <T extends IdentifiableBase> Map<String, T> mapById(List<T> identifiables) {
        Map<String, T> byId = new HashMap<>();

        for (T identifiable : identifiables) {
            byId.put(identifiable.getId(), identifiable);
        }

        return byId;
    }
}

        if (dominant == null || recessive == null) {
            return;
        }

        recessive.setSourceLevel(recessiveSourceLevel);

        List<String> dominantActiveProfiles = dominant.getActiveProfiles();
        List<String> recessiveActiveProfiles = recessive.getActiveProfiles();

        if (recessiveActiveProfiles != null) {
            if (dominantActiveProfiles == null) {
                dominantActiveProfiles = new ArrayList<>();
                dominant.setActiveProfiles(dominantActiveProfiles);
            }

            for (String profileId : recessiveActiveProfiles) {
                if (!dominantActiveProfiles.contains(profileId)) {
                    dominantActiveProfiles.add(profileId);
                }
            }
        }

        List<String> dominantPluginGroupIds = dominant.getPluginGroups();

        List<String> recessivePluginGroupIds = recessive.getPluginGroups();

        if (recessivePluginGroupIds != null) {
            if (dominantPluginGroupIds == null) {
                dominantPluginGroupIds = new ArrayList<>();
                dominant.setPluginGroups(dominantPluginGroupIds);
            }

            for (String pluginGroupId : recessivePluginGroupIds) {
                if (!dominantPluginGroupIds.contains(pluginGroupId)) {
                    dominantPluginGroupIds.add(pluginGroupId);
                }
            }
        }

        if (dominant.getLocalRepository() == null
                || dominant.getLocalRepository().isEmpty()) {
            dominant.setLocalRepository(recessive.getLocalRepository());
        }

        shallowMergeById(dominant.getMirrors(), recessive.getMirrors(), recessiveSourceLevel);
        shallowMergeById(dominant.getServers(), recessive.getServers(), recessiveSourceLevel);
        shallowMergeById(dominant.getProxies(), recessive.getProxies(), recessiveSourceLevel);
        shallowMergeById(dominant.getProfiles(), recessive.getProfiles(), recessiveSourceLevel);
        shallowMergeById(dominant.getRepositories(), recessive.getRepositories(), recessiveSourceLevel);
        shallowMergeById(dominant.getPluginRepositories(), recessive.getPluginRepositories(), recessiveSourceLevel);
    
<no_super_class>