概述
ShopService接口中仅需要定义一个接口方法，在该接口方法的实现类中调用DAO层的两个方法 selectShopList 和 selectShopCount ，并将数据封装到ShopExecution中，以便控制层获取数据，在View层做展示。
ShopExecution 这里增加了一个空构造函数，方便实例化并调用set方法，将shopList和shopCount 封装到ShopExecution 中
ShopService接口新增接口方法
/**
*
*
* @Title: getShopList
*
* @Description: 获取商铺列表. 在这一个方法中同样的会调用查询总数的DAO层方法，封装到ShopExecution中
*
* @param shopCondition
* @param pageIndex
* 前端页面 只有第几页 第几页 定义为pageIndex
* @param pageSize
* 展示的行数
* @throws ShopOperationException
*
* @return: ShopExecution
*/
ShopExecution getShopList(Shop shopCondition, int pageIndex, int pageSize) throws ShopOperationException;;ShopServie接口实现类
@Override
public ShopExecution getShopList(Shop shopCondition, int pageIndex, int pageSize) throws ShopOperationException {
// 前台页面插入的pageIndex（第几页）， 而dao层是使用 rowIndex （第几行） ，所以需要转换一下
int rowIndex = PageCalculator.calculateRowIndex(pageIndex, pageSize);
List<Shop> shopList = new ArrayList<Shop>();
ShopExecution se = new ShopExecution();
// 查询带有分页的shopList
shopList = shopDao.selectShopList(shopCondition, rowIndex, pageSize);
// 查询符合条件的shop总数
int count = shopDao.selectShopCount(shopCondition);
// 将shopList和 count设置到se中，返回给控制层
if (shopList != null) {
se.setShopList(shopList);
se.setCount(count);
} else {
se.setState(ShopStateEnum.INNER_ERROR.getState());
}
return se;
}分页工具类
负责将前台的PageIndex转换为DAO层的rowIndex.
package com.artisan.o2o.util;
/**
*
*
* @ClassName: PageCalculator
*
* @Description: 将前台使用的pageIndex 转换为 dao层使用的 rowIndex
*
* @author: Mr.Yang
*
* @date: 2018年6月7日 上午12:24:38
*/
public class PageCalculator {
public static int calculateRowIndex(int pageIndex, int pageSize) {
return (pageIndex > 0) ? (pageIndex - 1) * pageSize : 0;
}
}单元测试
tb_shop中的数据
@Test
public void testGetShopList() {
Shop shopCondition = new Shop();
PersonInfo personInfo = new PersonInfo();
personInfo.setUserId(1L);
shopCondition.setOwner(personInfo);
shopCondition.setShopName("咖啡");
// 符合 shop_name like '%咖啡%' 且 owner_id =1 有3条数据，
// 第二个参数 和 第三个参数 从pageIndex=1 第一页取数据，取2条 pageSize=2
ShopExecution se = shopService.getShopList(shopCondition, 1, 2);
// 按照tb_shop中的数据筛选 符合条件的数据3条， 从第一页开始取2条，se.getShopList().size() 应该有2条数据，
Assert.assertNotNull(se);
Assert.assertEquals(2, se.getShopList().size());
Assert.assertEquals(3, se.getCount());
// 按照tb_shop中的数据筛选 符合条件的数据3条， 从第2页开始取2条，se.getShopList().size()
// 应该只有1条数据，总数仍为3
se = shopService.getShopList(shopCondition, 2, 2);
Assert.assertNotNull(se);
Assert.assertEquals(1, se.getShopList().size());
Assert.assertEquals(3, se.getCount());
}
JDBC Connection [com.mchange.v2.c3p0.impl.NewProxyConnection@24ba9639] will not be managed by Spring
==> Preparing: SELECT s.shop_id, s.shop_name, s.shop_desc, s.shop_addr, s.phone, s.shop_img, s.priority, s.create_time, s.last_edit_time, s.enable_status, s.advice, a.area_id, a.area_name, sc.shop_category_id, sc.shop_category_name FROM tb_shop s, tb_area a, tb_shop_category sc WHERE s.shop_name like '%咖啡%' and s.owner_id = ? AND s.area_id = a.area_id AND s.shop_category_id = sc.shop_category_id ORDER BY s.priority DESC LIMIT ? , ?
==> Parameters: 1(Long), 0(Integer), 2(Integer)
<== Columns: shop_id, shop_name, shop_desc, shop_addr, phone, shop_img, priority, create_time, last_edit_time, enable_status, advice, area_id, area_name, shop_category_id, shop_category_name
<== Row: 24, 咖啡点, 小工匠的咖啡店, NanJing, 9876553, \upload\item\shopImage\24\2018052118095757182.jpg, 99, 2018-05-21 18:09:57.0, 2018-05-21 18:09:57.0, 0, 审核中, 1, 北京, 1, 咖啡奶茶
<== Row: 25, 咖啡店Improve, 小工匠的咖啡店Improve, NanJing-Improve, 9876553, \upload\item\shopImage\25\2018052214472089649.jpg, 99, 2018-05-22 14:46:16.0, 2018-05-22 14:46:18.0, 0, 审核中Improve, 1, 北京, 1, 咖啡奶茶
<== Total: 2
Closing non transactional SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@74bf1791]
Creating a new SqlSession
SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@12f9af83] was not registered for synchronization because synchronization is not active
JDBC Connection [com.mchange.v2.c3p0.impl.NewProxyConnection@7e6ef134] will not be managed by Spring
==> Preparing: SELECT count(1) FROM tb_shop s, tb_area a, tb_shop_category sc WHERE s.shop_name like '%咖啡%' and s.owner_id = ? AND s.area_id = a.area_id AND s.shop_category_id = sc.shop_category_id
==> Parameters: 1(Long)
<== Columns: count(1)
<== Row: 3
<== Total: 1
Closing non transactional SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@12f9af83]
Creating a new SqlSession
SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@7f132176] was not registered for synchronization because synchronization is not active
JDBC Connection [com.mchange.v2.c3p0.impl.NewProxyConnection@2631f68c] will not be managed by Spring
==> Preparing: SELECT s.shop_id, s.shop_name, s.shop_desc, s.shop_addr, s.phone, s.shop_img, s.priority, s.create_time, s.last_edit_time, s.enable_status, s.advice, a.area_id, a.area_name, sc.shop_category_id, sc.shop_category_name FROM tb_shop s, tb_area a, tb_shop_category sc WHERE s.shop_name like '%咖啡%' and s.owner_id = ? AND s.area_id = a.area_id AND s.shop_category_id = sc.shop_category_id ORDER BY s.priority DESC LIMIT ? , ?
==> Parameters: 1(Long), 2(Integer), 2(Integer)
<== Columns: shop_id, shop_name, shop_desc, shop_addr, phone, shop_img, priority, create_time, last_edit_time, enable_status, advice, area_id, area_name, shop_category_id, shop_category_name
<== Row: 28, Modify咖啡店, Modify小工匠的咖啡店28, Modify-NanJing218, 12345628, \upload\item\shopImage\28\2018060500333541696.jpg, 78, 2018-05-28 23:13:37.0, 2018-06-06 20:56:31.0, 0, null, 2, 上海, 2, 咖啡
<== Total: 1
Closing non transactional SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@7f132176]
Creating a new SqlSession
SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@bcef303] was not registered for synchronization because synchronization is not active
JDBC Connection [com.mchange.v2.c3p0.impl.NewProxyConnection@33308786] will not be managed by Spring
==> Preparing: SELECT count(1) FROM tb_shop s, tb_area a, tb_shop_category sc WHERE s.shop_name like '%咖啡%' and s.owner_id = ? AND s.area_id = a.area_id AND s.shop_category_id = sc.shop_category_id
==> Parameters: 1(Long)
<== Columns: count(1)
<== Row: 3
<== Total: 1
Closing non transactional SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@bcef303]