/**
* Parses object with follow rules:
*
* <p>1. All fields should had a public access. 2. The name of the filed should be fully equal to
* name of JSONObject key. 3. Supports parse of all Java primitives, all {@link String}, arrays of
* primitive types, {@link String}s and {@link com.vk.sdk.api.model.VKApiModel}s, list
* implementation line {@link VKList}, {@link com.vk.sdk.api.model.VKAttachments.VKAttachment} or
* {@link com.vk.sdk.api.model.VKPhotoSizes}, {@link com.vk.sdk.api.model.VKApiModel}s.
*
* <p>4. Boolean fields defines by vk_int == 1 expression.
*
* @param object object to initialize
* @param source data to read values
* @param <T> type of result
* @return initialized according with given data object
* @throws org.json.JSONException if source object structure is invalid
*/
@SuppressWarnings({"rawtypes", "unchecked"})
public static <T> T parseViaReflection(T object, JSONObject source) throws JSONException {
if (source.has("response")) {
source = source.optJSONObject("response");
}
if (source == null) {
return object;
}
for (Field field : object.getClass().getFields()) {
field.setAccessible(true);
String fieldName = field.getName();
Class<?> fieldType = field.getType();
Object value = source.opt(fieldName);
if (value == null) {
continue;
}
try {
if (fieldType.isPrimitive() && value instanceof Number) {
Number number = (Number) value;
if (fieldType.equals(int.class)) {
field.setInt(object, number.intValue());
} else if (fieldType.equals(long.class)) {
field.setLong(object, number.longValue());
} else if (fieldType.equals(float.class)) {
field.setFloat(object, number.floatValue());
} else if (fieldType.equals(double.class)) {
field.setDouble(object, number.doubleValue());
} else if (fieldType.equals(boolean.class)) {
field.setBoolean(object, number.intValue() == 1);
} else if (fieldType.equals(short.class)) {
field.setShort(object, number.shortValue());
} else if (fieldType.equals(byte.class)) {
field.setByte(object, number.byteValue());
}
} else {
Object result = field.get(object);
if (value.getClass().equals(fieldType)) {
result = value;
} else if (fieldType.isArray() && value instanceof JSONArray) {
result = parseArrayViaReflection((JSONArray) value, fieldType);
} else if (VKPhotoSizes.class.isAssignableFrom(fieldType) && value instanceof JSONArray) {
Constructor<?> constructor = fieldType.getConstructor(JSONArray.class);
result = constructor.newInstance((JSONArray) value);
} else if (VKAttachments.class.isAssignableFrom(fieldType)
&& value instanceof JSONArray) {
Constructor<?> constructor = fieldType.getConstructor(JSONArray.class);
result = constructor.newInstance((JSONArray) value);
} else if (VKList.class.equals(fieldType)) {
ParameterizedType genericTypes = (ParameterizedType) field.getGenericType();
Class<?> genericType = (Class<?>) genericTypes.getActualTypeArguments()[0];
if (VKApiModel.class.isAssignableFrom(genericType)
&& Parcelable.class.isAssignableFrom(genericType)
&& Identifiable.class.isAssignableFrom(genericType)) {
if (value instanceof JSONArray) {
result = new VKList((JSONArray) value, genericType);
} else if (value instanceof JSONObject) {
result = new VKList((JSONObject) value, genericType);
}
}
} else if (VKApiModel.class.isAssignableFrom(fieldType) && value instanceof JSONObject) {
result = ((VKApiModel) fieldType.newInstance()).parse((JSONObject) value);
}
field.set(object, result);
}
} catch (InstantiationException e) {
throw new JSONException(e.getMessage());
} catch (IllegalAccessException e) {
throw new JSONException(e.getMessage());
} catch (NoSuchMethodException e) {
throw new JSONException(e.getMessage());
} catch (InvocationTargetException e) {
throw new JSONException(e.getMessage());
} catch (NoSuchMethodError e) {
// Примечание Виталия:
// Вы не поверите, но у некоторых вендоров getFields() вызывает ВОТ ЭТО.
// Иногда я всерьез задумываюсь, правильно ли я поступил, выбрав Android в качестве
// платформы разработки.
throw new JSONException(e.getMessage());
}
}
return object;
}
