java中一个查询业务的流程
因为有用到分页,首先建一个page类
1 public class Page<T> { 2 private int pageSize; //每页显示条数 3 private int curPage = 1; //当前页,默认从1开始 4 private long total; //总记录数 5 private int pages; //总页数 6 private List<T> list; //页面列表数据 7 public Page() { 8 pageSize = 5; //默认5条每页 9 } 10 //获取第一条的数码 11 public int getStarPage(){ 12 int starPage = pageSize * (curPage-1); 13 return starPage; 14 } 15 public int getPageSize() { 16 return pageSize; 17 } 18 // 所有属性的get ,set方法 ...... 45 }
然后在控制层中,控制层接收到请求/order/do
@Controller @RequestMapping("/order") public class OrderController{ @Resource private OrderService OrderService @RequestMapping(value = "/do",method = RequestMethod.GET)
//这里的c是状态属性,值为0或1 public String getList(@RequestParam(value="b",defaultValue="0") int b,@RequestParam(value="c",defaultValue="0") int c, Page<Order> page,HttpServletRequest request,HttpServletResponse response,Model model) { System.out.println(page.getCurPage()); Page<Order> OrderPage=new Page<Order>(); //判断是否有页码的输入,没有使用默认的 if(page.getCurPage()!=0){ OrderPage.setCurPage(page.getCurPage()); OrderPage.setPageSize(page.getPageSize()); } //我们需要的记录 java.util.List<Order> rval = OrderService.getlist(1,OrderPage.getStarPage(),OrderPage.getPageSize()); //查询XService表的总记录 OrderPage.setTotal(OrderService.queryToalOrder(1); // System.out.println(page.getTotal()); OrderPage.setPages((int)OrderPage.getTotal()/OrderPage.getPageSize()); // System.out.println(XPage.getPages()); Orderpage.setList(rval); model.addAttribute("OrderPage", OrderPage);if(b==0){ return "Manager"; }else if(c==0){ return "already"; }else if(c==1){ return "will"; }else return null; } }
service层中
@Service public classOrderService { @Resource private OrderMapper orderMapper; //查询Order总记录的条数 @Transactional(propagation = Propagation.SUPPORTS,readOnly = true) public int queryToalOrder(int sta,){ return OrderMapper.queryToalOrder(sta); } //我们需要的记录 @Transactional(propagation = Propagation.SUPPORTS,readOnly = true) public java.util.List<Order> getlist(int sta,int starPage,int pageSize) { return shuttleOrderMapper.getlist(sta,starPage,pageSize); } }
然后进入dao层
public interface OrderMapper{ //查询Order总记录的条数 int queryToalOrder(@Param("sta")int sta); //我们需要的记录 java.util.List<Order> getlist(@Param("sta")int sta,@Param("starPage")int starPage,@Param("pageSize") int pageSize); }
然后找到对应的sql语句
<?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.leederedu.educhat.modules.sys.dao.ShuttleOrderMapper">
<!-- 查询我们要的记录 -->
<select id="getlist" resultType="Order">
select a,b,c,d,e,f,g from test t where t.sta=#{sta} limit #{starPage},#{pageSize};
</select>
<!--查询Order总记录的条数 -->
<select id="queryToalOrder" resultType="int">
select count(*) from test t where t.sta=#{sta}
</select>
</mapper>
然后jsp中获取到对应的值展示即可。
随手笔记,如有错误鄙人将很感激您的提出。