Bean和Map互轉

Bean和Map互轉

import com.alibaba.fastjson.JSONObject;

import java.beans.BeanInfo;
import java.beans.Introspector;
import java.beans.PropertyDescriptor;
import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

public class BeanUtils {

    public static <T> List<T> mapListToBeanList(List<Map> mapList, Class<T> beanClass) {
        List<T> list = new ArrayList<>();
        if (mapList != null && mapList.size() > 0) {
            for (Map item : mapList) {
                T bean = new JSONObject(item).toJavaObject(beanClass);
                list.add(bean);
            }
        }
        return list;
    }

    public static <T> T mapToBean(Map map, Class<T> beanClass) {
        if (map == null) {
            return null;
        }
        return new JSONObject(map).toJavaObject(beanClass);
    }

    public static List<Map> beanListToMapList(List objList) {
        List<Map> list = new ArrayList<>();
        if (objList != null && objList.size() > 0) {
            for (Object obj : objList) {
                Map bean = beanToMap(obj);
                list.add(bean);
            }
        }
        return list;
    }

    // Bean --> Map 
    public static Map<String, Object> beanToMap(Object obj) {
        if (obj == null) {
            return null;
        }
        Map<String, Object> map = new HashMap<String, Object>();
        try {
            BeanInfo beanInfo = Introspector.getBeanInfo(obj.getClass());
            PropertyDescriptor[] propertyDescriptors = beanInfo.getPropertyDescriptors();
            for (PropertyDescriptor property : propertyDescriptors) {
                String key = property.getName();
                // 過濾class屬性
                if (!key.equals("class")) {
                    // 得到property對應的getter方法
                    Method getter = property.getReadMethod();
                    Object value = getter.invoke(obj);

                    map.put(key, value);
                }

            }
        } catch (Exception e) {
            throw new RuntimeException("Bean轉Map失敗", e);
        }
        return map;
    }
}

List<Map> 排序

Collections.sort(list, new Comparator<Map<String, Object>>() {
                        public int compare(Map<String, Object> o1, Map<String, Object> o2) {
                            Date createDate1 = (Date) o1.get("createDate");
                            Date createDate2 = (Date) o2.get("createDate");
                            // 倒序
                            return createDate2.compareTo(createDate1);
                        }
                    });