Class JSONUtil

src/main/java/com/oltpbenchmark/util/JSONUtil.java:39–645

@author pavlo

 * @author pavlo
 */
public abstract class JSONUtil {
  private static final Logger LOG = LoggerFactory.getLogger(JSONUtil.class.getName());

  private static final String JSON_CLASS_SUFFIX = "_class";
  private static final Map<Class<?>, Field[]> SERIALIZABLE_FIELDS = new HashMap<>();

  /**
   * @param clazz
   * @return
   */
  public static Field[] getSerializableFields(Class<?> clazz, String... fieldsToExclude) {
    Field[] ret = SERIALIZABLE_FIELDS.get(clazz);
    if (ret == null) {
      Collection<String> exclude = CollectionUtil.addAll(new HashSet<>(), fieldsToExclude);
      synchronized (SERIALIZABLE_FIELDS) {
        ret = SERIALIZABLE_FIELDS.get(clazz);
        if (ret == null) {
          List<Field> fields = new ArrayList<>();
          for (Field f : clazz.getFields()) {
            int modifiers = f.getModifiers();
            if (!Modifier.isTransient(modifiers)
                && Modifier.isPublic(modifiers)
                && !Modifier.isStatic(modifiers)
                && !exclude.contains(f.getName())) {
              fields.add(f);
            }
          }
          ret = fields.toArray(new Field[0]);
          SERIALIZABLE_FIELDS.put(clazz, ret);
        }
      }
    }
    return (ret);
  }

  /**
   * JSON Pretty Print
   *
   * @param json
   * @return
   * @throws JSONException
   */
  public static String format(String json) {
    try {
      return (JSONUtil.format(
          new JSONObject(json) {
            /**
             * changes the value of JSONObject.map to a LinkedHashMap in order to maintain order of
             * keys. See Also: https://stackoverflow.com/a/62476486
             */
            @Override
            public JSONObject put(String key, Object value) throws JSONException {
              try {
                Field map = JSONObject.class.getDeclaredField("map");
                map.setAccessible(true);
                Object mapValue = map.get(this);
                if (!(mapValue instanceof LinkedHashMap)) {
                  map.set(this, new LinkedHashMap<>());