对比两个集合哪些是新增，哪些是修改，哪些是删除工具类

package com.heima.article;

import cn.hutool.core.util.ReflectUtil;

import java.util.ArrayList;
import java.util.List;
import java.util.stream.Collectors;

public class NewOldComparer<T> {
    private List<T> insertIds = new ArrayList<T>();

    private List<T> updateIds = new ArrayList<T>();

    private List<T> deleteIds = new ArrayList<T>();

    public NewOldComparer(List<T> newIds, List<T> oldIds) {
        if (null != newIds && newIds.size() > 0) {
            hasNewIds(newIds, oldIds);
        } else {
            noHasNewIds(oldIds);
        }
    }

    public List<T> insertIds() {
        return insertIds;
    }

    public List<T> updateIds() {
        return updateIds;
    }

    public List<T> deleteIds() {
        return deleteIds;
    }

    private void hasNewIds(List<T> newIds, List<T> oldIds) {
        if (oldIds.size() == 0) {
            this.insertIds = newIds;
        } else {
            for (T newId : newIds) {
                Integer id = (Integer) ReflectUtil.getFieldValue(newId, "id");
                if (id == null) {
                    this.insertIds.add(newId);
                } else {
                    this.updateIds.add(newId);
                }
            }
            List<Object> newIdList = newIds.stream().map(s -> ReflectUtil.getFieldValue(s, "id")).collect(Collectors.toList());
            List<Integer> newIdsList = new ArrayList<>(newIdList.size());
            newIdList.forEach(s->{
                newIdsList.add((Integer)s);
            });
            for (T oldId : oldIds) {
                Integer id = (Integer) ReflectUtil.getFieldValue(oldId, "id");
                if (!newIdList.contains(id)){
                    this.deleteIds.add(oldId);
                }
            }
        }
    }

    private void noHasNewIds(List<T> oldIds) {
        if (null != oldIds && oldIds.size() > 0) {
            this.deleteIds = oldIds;
        }
    }
}