一个类通过id关联另一个类，前后台处理

后台：package com.gxzhuangxing.base.modules.advertise.entity;import java.util.Date;import com.fasterxml.jackson.annotation.JsonFormat;import com.gxzhuangxing.base.common.persistence.Entity;import com.gxzhuangxing.base.common.utils.SpringContextHolder;import com.gxzhuangxing.base.modules.advertise.service.AdvertiseLocationService;/** * 广告管理 * @author  * */public class Advertise{private AdvertiseLocationService advertiseLocationService =SpringContextHolder.getBean(AdvertiseLocationService.class);       /** * 名称 */private String title;       /**        * 另一个类的ID        */        private long advertiseLocationId;public Advertise(){}public String getTitle() {return title;}public void setTitle(String title) {this.title = title;}        public long getAdvertiseLocationId() {                return advertiseLocationId;        }        public void setAdvertiseLocationId(long advertiseLocationId) {                this.advertiseLocationId = advertiseLocationId;        }public AdvertiseLocation getAdvertiseLocation() {return advertiseLocationService.get(advertiseLocationId);}}前台接收到 Advertise对象  后  可在<pre name="code" class="java">advertise.advertiseLocation   得到另一个类对象及其内部属性值。