旅游线路分页展示_分页数据展示_代码实现_Servlet与旅游线路分页展示_分页数据展示_代码实现_Dao

旅游线路分页展示_分页数据展示_代码实现_Servlet

　　　RouteServlet:　　　

package cn.itcast.travel.web.servlet;

import cn.itcast.travel.domain.PageBean;
import cn.itcast.travel.domain.Route;
import cn.itcast.travel.service.RouteService;
import cn.itcast.travel.service.impl.RouteServiceImpl;

import javax.servlet.*;
import javax.servlet.http.*;
import javax.servlet.annotation.*;
import java.io.IOException;

@WebServlet("/route/*")
public class RouteServlet extends BaseServlet {

    private RouteService routeService = new RouteServiceImpl();

    /**
     * 分页查询
     * @param request
     * @param response
     * @throws ServletException
     * @throws IOException
     */
    public void pageQuery(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        //1.接受参数
        String currentPageStr = request.getParameter("currentPage");
        String pageSizeStr = request.getParameter("pageSize");
        String cidStr = request.getParameter("cid");

        int cid = 0;//类别id
        //2.处理参数
        if(cidStr != null && cidStr.length() > 0){
            cid = Integer.parseInt(cidStr);
        }
        int currentPage = 0;//当前页码，如果不传递，则默认为第一页
        if(currentPageStr != null && currentPageStr.length() > 0){
            currentPage = Integer.parseInt(currentPageStr);
        }else{
            currentPage = 1;
        }

        int pageSize = 0;//每页显示条数，如果不传递，默认每页显示5条记录
        if(pageSizeStr != null && pageSizeStr.length() > 0){
            pageSize = Integer.parseInt(pageSizeStr);
        }else{
            pageSize = 5;
        }

        //3. 调用service查询PageBean对象
        PageBean<Route> pb = routeService.pageQuery(cid, currentPage, pageSize);

        //4. 将pageBean对象序列化为json，返回
        writeValue(pb,response);

    }

}

RouteService:

package cn.itcast.travel.service;

import cn.itcast.travel.domain.PageBean;
import cn.itcast.travel.domain.Route;

/**
 * 线路Service
 */
public interface RouteService {
    /**
     * 根据类别进行分页查询
     * @param cid
     * @param currentPage
     * @param pageSize
     * @return
     */
    PageBean<Route> pageQuery(int cid, int currentPage, int pageSize);
}

RouteServiceImpl :

package cn.itcast.travel.service.impl;


import cn.itcast.travel.domain.PageBean;
import cn.itcast.travel.domain.Route;
import cn.itcast.travel.service.RouteService;


public class RouteServiceImpl implements RouteService {

    @Override
    public PageBean<Route> pageQuery(int cid, int currentPage, int pageSize) {
        return null;
    }
}

旅游线路分页展示_分页数据展示_代码实现_Dao

package cn.itcast.travel.dao;

import cn.itcast.travel.domain.Route;

import java.util.List;

public interface RouteDao {

    /**
     * 根据cid查询总记录
     */

    public int findTotalCount(int cid);


    /**
     * 根据cid、start、pageSize查询当前页的数据集合
     */

    public List<Route> findByPage(int cid,int start,int pageSize);
}

package cn.itcast.travel.dao.impl;

import cn.itcast.travel.dao.RouteDao;
import cn.itcast.travel.domain.Route;
import cn.itcast.travel.util.JDBCUtils;
import org.springframework.jdbc.core.BeanPropertyRowMapper;
import org.springframework.jdbc.core.JdbcTemplate;

import java.util.List;

public class RouteDaoImpl implements RouteDao {
    private JdbcTemplate template = new JdbcTemplate(JDBCUtils.getDataSource());

    @Override
    public int findTotalCount(int cid) {
        String sql = "select count(*) from tab_route where cid = ?";
        return template.queryForObject(sql,Integer.class,cid);
    }

    @Override
    public List<Route> findByPage(int cid, int start, int pageSize) {
        String sql = "select * from tab_route where cid = ? limit ?,?";

        return template.query(sql,new BeanPropertyRowMapper<>(Route.class),cid,start,pageSize);
    }
}