public static Map<String, String> maptoMapString(Map<String, ?> map) {
     return map.entrySet().stream().collect(Collectors.toMap(
            (entry) -> {
                return entry.getKey();
            },
            (entry) -> {
                if(entry.getValue().getClass().isArray()) {
                    StringBuilder sb = new StringBuilder();
                    for(int i=0; i<Array.getLength(entry.getValue()); ++i) {
                        Object obj = Array.get(entry.getValue(), i);
                        sb.append(obj.toString()).append(",");
                    }
                    if (sb.length() > 0) {
                        sb.deleteCharAt(sb.length() - 1);
                    }

                    return sb.toString();
                } else {
                    return entry.getValue().toString();
                }
            }
    ));
}