/*
* Copyright 2014 Higher Frequency Trading
*
* http://www.higherfrequencytrading.com
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package net.openhft.lang.io.serialization.direct;
import net.openhft.lang.Maths;
import java.lang.reflect.Field;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.List;
import static net.openhft.lang.io.NativeBytes.UNSAFE;
import static net.openhft.lang.io.serialization.direct.FieldMetadata.isStatic;
public class Introspect {
public static List<Field> fields(Class<?> clazz) {
ArrayList<Field> fields = new ArrayList<Field>();
addToFields(clazz, fields);
Collections.sort(fields, FieldOffsetComparator.Instance);
return fields;
}
private static List<Field> addToFields(Class<?> clazz, ArrayList<Field> accumulator) {
Collections.addAll(accumulator, clazz.getDeclaredFields());
Class<?> maybeSuper = clazz.getSuperclass();
return maybeSuper != null ?
addToFields(maybeSuper, accumulator) :
accumulator;
}
private static final class FieldOffsetComparator implements Comparator<Field> {
public static final FieldOffsetComparator Instance = new FieldOffsetComparator();
@Override
public int compare(Field first, Field second) {
return Maths.compare(offset(first), offset(second));
}
private static long offset(Field field) {
return isStatic(field) ?
UNSAFE.staticFieldOffset(field) :
UNSAFE.objectFieldOffset(field);
}
}
}