I have the below function for deserialization. I am passing an object to obj field. If one of the value in object is empty string it gives me a null pointer exception. How can I avoid this situation?
public static MultiValueMap convertFilterToMultiValueMap(ObjectMapper objectMapper, Object obj) {
        MultiValueMap parameters = new LinkedMultiValueMap();
        Map<String, Object> map = (Map)objectMapper.convertValue(obj, new TypeReference<Map<String, Object>>() {
        });
        map.forEach((key, value) -> {
            if (value instanceof List) {
                ((List)value).forEach((item) -> {
                    map.put(key, item.toString());
                });
            } else {
                map.put(key, value.toString());
            }
        });
        parameters.setAll(map);
        return parameters;
    }
