shop--11.前端展示系统--首页展示（后端）

概述

接下来我们来完成前端展示模块部分的功能

可以分析得出，主页中轮播图需要从后台加载数据，同样的一级类别（即parent_id = null ）的商铺信息也需要从后台加载数据

HeadLineDao.java

    /**
     * 根据传入的查询条件（头条名查询头条）
     * 
     * @param headLineCondition
     * @return
     */
    List<HeadLine> queryHeadLine(@Param("headLineCondition")HeadLine headLineCondition); 

HeadLineDao.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper 
  PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" 
  "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.ryanxu.o2o.dao.HeadLineDao">
    <select id="queryHeadLine" resultType="com.ryanxu.o2o.entity.HeadLine">
        SELECT
        line_id,
        line_name,
        line_link,
        line_img,
        priority,
        enable_status,
        create_time,
        last_edit_time
        FROM
        tb_head_line
        <where>
            <if test="headLineCondition.enableStatus!=null">
                and enable_status = #{headLineCondition.enableStatus}
            </if>
        </where>
        ORDER BY
        priority DESC
    </select>

</mapper>

ShopCategoryDao.xml

因为之前的queryShopCategory 只支持返回parent_id不为空的情况 做个补充 加入parent_id可以为空的情况

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper 
  PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" 
  "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.ryanxu.o2o.dao.ShopCategoryDao">
    <select id="queryShopCategory"
        resultType="com.ryanxu.o2o.entity.ShopCategory">
        SELECT
        shop_category_id,
        shop_category_name,
        shop_category_desc,
        shop_category_img,
        priority,
        create_time,
        last_edit_time,
        parent_id
        FROM
        tb_shop_category
        <where>
            <if test="shopCategoryCondition == null">
                and parent_id is null
            </if>
            <if test="shopCategoryCondition != null">
                and parent_id is not null
            </if>
            <if
                test="shopCategoryCondition !=null and shopCategoryCondition.parent!=null">
                and parent_id = #{shopCategoryCondition.parent.shopCategoryId}
            </if>
        </where>
        ORDER BY
        priority DESC
    </select>
</mapper>

HeadLineService.java

public interface HeadLineService {
    /**
     * 根据传入的条件返回指定的头条列表
     * 
     * @param headLineCondition
     * @return
     * @throws IOException
     */
    List<HeadLine> getHeadLineList(HeadLine headLineCondition) throws IOException;
}

HeadLineServiceImpl.java

@Service
public class HeadLineServiceImpl implements HeadLineService{

    @Autowired
    private HeadLineDao headLineDao;
    
    @Override
    public List<HeadLine> getHeadLineList(HeadLine headLineCondition) throws IOException {
        return headLineDao.queryHeadLine(headLineCondition);
    }
    
}

MainPageController.java

@Controller
@RequestMapping(value="/frontend")
public class MainPageController {
    @Autowired
    private HeadLineService headLineService;
    @Autowired
    private ShopCategoryService shopCategoryService;
    
    /**
     * 初始化前端展示系统的主页信息，包括获取一级店铺类别列表以及头条列表
     * 
     * @return
     */
    @RequestMapping(value="/listmainpageinfo",method=RequestMethod.GET)
    @ResponseBody
    private Map<String, Object> listMainPageInfo(){
        Map<String, Object> modelMap = new HashMap<String, Object>();
        List<ShopCategory> shopCategoryList = new ArrayList<ShopCategory>();
        try {
            //获取以及店铺类别列表（即parentId为空的ShopCategory）
            shopCategoryList = shopCategoryService.getShopCategoryList(null);
            modelMap.put("shopCategoryList", shopCategoryList);
        }catch (Exception e) {
            modelMap.put("success", false);
            modelMap.put("errMsg", e.getMessage());
            return modelMap;
        }
        List<HeadLine> headLineList = new ArrayList<HeadLine>();
        try {
            //获取状态为可用（1）的头条列表
            HeadLine headLineCondition = new HeadLine();
            headLineCondition.setEnableStatus(1);
            headLineList = headLineService.getHeadLineList(headLineCondition);
            modelMap.put("headLineList", headLineList);
        }catch (Exception e) {
            modelMap.put("success", false);
            modelMap.put("errMsg", e.getMessage());
            return modelMap;
        }
        modelMap.put("success", true);
        return modelMap;
    }
}