JacksonでJSONとListを相互変換する

JSON文字列をListに変換する

public static <T> List<T> convertToList(String json, Class<T> clazz) {
    List<T> list = null;
    if (!StringUtils.isEmpty(json)) {
        ObjectMapper mapper = new ObjectMapper();
        final CollectionType jt = mapper.getTypeFactory().constructCollectionType(List.class, clazz);
        try {
            list = mapper.readValue(json, jt);
        } catch (JsonProcessingException e) {
            e.printStackTrace();
        }
    }
    return list;
}

ListをJSON文字列に変換する

public static <T> String convertToJson(List<T> list) {
    ObjectMapper mapper = new ObjectMapper();
    String json = "";
    if (Objects.nonNull(list)) {
        try {
            json = mapper.writeValueAsString(list);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
    return json;
}