初识 Spring(20)---(SpringMVC实战--构建学生管理系统（10））
SpringMVC实战--构建学生管理系统（10）
首页部分课程管理页面（分页功能）制作（在上篇博客基础上继续）
（源代码见仓库：https://gitee.com/jianghao233/course）
思路：
1.前台可以给后台传递的数据：1.当前页 2.每页显示多少条记录
2.SQL分页语句：select * from tb_course LIMIT A,B (从A开始，显示B条)
制作分页：前端传递的是当前页，但后台需要的是从那一条数据开始查询 == （当前页数-1 *每页显示条数B）
录入信息：
制作分页功能：
修改代码：
新建Commons.java
package com.neuedu.commons;
public interface Commons {
//定义静态常量
//每页显示条数
public static final int RECORD = 5;
}
修改 index.jsp
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
修改 CourseService.java
package com.neuedu.service;
import java.util.List;
import com.neuedu.po.TbCourse;
public interface CourseService {
void save(TbCourse tbCourse);
TbCourse getCourseById(Integer courseid); //修改代码
List getList(Integer nowPage); //修改代码
void update(TbCourse tbCourse);
void delete(Integer courseid);
}
修改CourseServiceImpl.java
package com.neuedu.service.impl;
import java.util.List;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import com.neuedu.commons.Commons;
import com.neuedu.mapper.TbCourseMapper;
import com.neuedu.po.TbCourse;
import com.neuedu.service.CourseService;
@Service
public class CourseServiceImpl implements CourseService {
@Autowired
private TbCourseMapper courseMapper;
@Override
public void save(TbCourse tbCourse) {
courseMapper.insertSelective(tbCourse);
}
@Override
public List getList(Integer nowPage) { //修改代码
//获取每页显示条数
int record = Commons.RECORD; //新增代码
//通过计算得出从第几条开始查询
int start = (nowPage - 1) * record;
return courseMapper.getList(start,record); //新增代码
}
@Override
public TbCourse getCourseById(Integer courseid) {
return courseMapper.selectByPrimaryKey(courseid);
}
@Override
public void update(TbCourse tbCourse) {
courseMapper.updateByPrimaryKeySelective(tbCourse);
}
@Override
public void delete(Integer courseid) {
courseMapper.deleteByPrimaryKey(courseid);
}
}
修改TbCourseMapper.java
package com.neuedu.mapper;
import java.util.List;
import org.apache.ibatis.annotations.Param;
import com.neuedu.po.TbCourse;
public interface TbCourseMapper {
int deleteByPrimaryKey(Integer courseid);
int insert(TbCourse record);
int insertSelective(TbCourse record);
TbCourse selectByPrimaryKey(Integer courseid);
int updateByPrimaryKeySelective(TbCourse record);
int updateByPrimaryKey(TbCourse record);
public List getList(@Param("start") int start,@Param("record")int record);
//修改代码
} 修改TbCourseMapper.xml
courseid, coursename, hour, score, picurl
delete from tb_course
where courseid = #{courseid,jdbcType=INTEGER}
insert into tb_course (courseid, coursename, hour,
score, picurl)
values (#{courseid,jdbcType=INTEGER}, #{coursename,jdbcType=VARCHAR}, #{hour,jdbcType=INTEGER},
#{score,jdbcType=DOUBLE}, #{picurl,jdbcType=VARCHAR})
insert into tb_course
courseid,
coursename,
hour,
score,
picurl,
#{courseid,jdbcType=INTEGER},
#{coursename,jdbcType=VARCHAR},
#{hour,jdbcType=INTEGER},
#{score,jdbcType=DOUBLE},
#{picurl,jdbcType=VARCHAR},
update tb_course
coursename = #{coursename,jdbcType=VARCHAR},
hour = #{hour,jdbcType=INTEGER},
score = #{score,jdbcType=DOUBLE},
picurl = #{picurl,jdbcType=VARCHAR},
where courseid = #{courseid,jdbcType=INTEGER}
update tb_course
set coursename = #{coursename,jdbcType=VARCHAR},
hour = #{hour,jdbcType=INTEGER},
score = #{score,jdbcType=DOUBLE},
picurl = #{picurl,jdbcType=VARCHAR}
where courseid = #{courseid,jdbcType=INTEGER}
修改 CourseController.java
package com.neuedu.controller;
import java.util.List;
import java.util.Map;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.ResponseBody;
import com.neuedu.po.TbCourse;
import com.neuedu.service.CourseService;
import com.sun.javafx.css.CssError.InlineStyleParsingError;
@Controller
@RequestMapping("/course")
public class CourseController {
@Autowired
private CourseService courseService;
@RequestMapping({"/","/list"})
public String list(@RequestParam(value="nowPage",required=false,defaultValue="1") Integer nowPage,Model model) {
//查询课程列表 （修改代码）
List list = courseService.getList(nowPage); //修改代码
model.addAttribute("list",list);
return "admin/courseManager";
}
//显示添加页面
@RequestMapping("/showAdd")
public String showAdd() {
return "admin/courseAdd";
}
//保存课程信息
@RequestMapping("/save")
public String save(TbCourse tbCourse){
//调用service保存课程信息
courseService.save(tbCourse);
return "redirect:/course/";
}
//显示编辑页面
@RequestMapping("/showModify")
public String showModify(Integer courseid,Map map) {
TbCourse tbCourse = courseService.getCourseById(courseid);
map.put("c", tbCourse);
return "admin/courseModify";
}
@RequestMapping("/modify")
public String modify(TbCourse tbCourse) {
courseService.update(tbCourse);
return "redirect:/course/";
}
@RequestMapping("/delete")
public String delete(Integer courseid) {
courseService.delete(courseid);
return "redirect:/course/";
}
}
输出：在代码中，当前页为 1 ，每页显示 5 条 ，即可得到如图页面
但这时目录是写死的，后台也应该向前台传递数据，要能够跳转到第二页去，当前页也要随着修改，继续修改代码
修改代码修改TbCourseMapper.java
package com.neuedu.mapper;
import java.util.List;
import org.apache.ibatis.annotations.Param;
import com.neuedu.po.TbCourse;
public interface TbCourseMapper {
int deleteByPrimaryKey(Integer courseid);
int insert(TbCourse record);
int insertSelective(TbCourse record);
TbCourse selectByPrimaryKey(Integer courseid);
int updateByPrimaryKeySelective(TbCourse record);
int updateByPrimaryKey(TbCourse record);
public List getList(@Param("start") int start,@Param("record")int record);
public int getCount(); //新增代码
} 修改 修改TbCourseMapper.xml
courseid, coursename, hour, score, picurl
delete from tb_course
where courseid = #{courseid,jdbcType=INTEGER}
insert into tb_course (courseid, coursename, hour,
score, picurl)
values (#{courseid,jdbcType=INTEGER}, #{coursename,jdbcType=VARCHAR}, #{hour,jdbcType=INTEGER},
#{score,jdbcType=DOUBLE}, #{picurl,jdbcType=VARCHAR})
insert into tb_course
courseid,
coursename,
hour,
score,
picurl,
#{courseid,jdbcType=INTEGER},
#{coursename,jdbcType=VARCHAR},
#{hour,jdbcType=INTEGER},
#{score,jdbcType=DOUBLE},
#{picurl,jdbcType=VARCHAR},
update tb_course
coursename = #{coursename,jdbcType=VARCHAR},
hour = #{hour,jdbcType=INTEGER},
score = #{score,jdbcType=DOUBLE},
picurl = #{picurl,jdbcType=VARCHAR},
where courseid = #{courseid,jdbcType=INTEGER}
update tb_course
set coursename = #{coursename,jdbcType=VARCHAR},
hour = #{hour,jdbcType=INTEGER},
score = #{score,jdbcType=DOUBLE},
picurl = #{picurl,jdbcType=VARCHAR}
where courseid = #{courseid,jdbcType=INTEGER}
//新增代码
修改 CourseService.java
package com.neuedu.service;
import java.util.List;
import com.neuedu.po.TbCourse;
public interface CourseService {
void save(TbCourse tbCourse);
TbCourse getCourseById(Integer courseid);
List getList(Integer nowPage);
void update(TbCourse tbCourse);
void delete(Integer courseid);
int getCount(); //新增代码
}
修改CourseServiceImpl.java
package com.neuedu.service.impl;
import java.util.List;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import com.neuedu.commons.Commons;
import com.neuedu.mapper.TbCourseMapper;
import com.neuedu.po.TbCourse;
import com.neuedu.service.CourseService;
@Service
public class CourseServiceImpl implements CourseService {
@Autowired
private TbCourseMapper courseMapper;
@Override
public void save(TbCourse tbCourse) {
courseMapper.insertSelective(tbCourse);
}
@Override
public List getList(Integer nowPage) {
//获取每页显示条数
int record = Commons.RECORD;
//通过计算得出从第几条开始查询
int start = (nowPage - 1) * record;
return courseMapper.getList(start,record);
}
@Override
public TbCourse getCourseById(Integer courseid) {
return courseMapper.selectByPrimaryKey(courseid);
}
@Override
public void update(TbCourse tbCourse) {
courseMapper.updateByPrimaryKeySelective(tbCourse);
}
@Override
public void delete(Integer courseid) {
courseMapper.deleteByPrimaryKey(courseid);
}
@Override
public int getCount() { //新增代码
return courseMapper.getCount();
} //新增代码
}
修改CourseController.java
package com.neuedu.controller;
import java.util.List;
import java.util.Map;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.ResponseBody;
import com.neuedu.commons.Commons;
import com.neuedu.po.TbCourse;
import com.neuedu.service.CourseService;
import com.sun.javafx.css.CssError.InlineStyleParsingError;
@Controller
@RequestMapping("/course")
public class CourseController {
@Autowired
private CourseService courseService;
@RequestMapping({"/","/list"})
public String list(@RequestParam(value="nowPage",required=false,defaultValue="1") Integer nowPage,Model model) {
//查询课程列表
List list = courseService.getList(nowPage);
//总课程数
int count = courseService.getCount(); //新增代码
//总页数
int totalPage = (int)Math.ceil(((double)count)/Commons.RECORD); //新增代码
model.addAttribute("list",list); //新增代码
model.addAttribute("nowPage",nowPage);
model.addAttribute("count",count);
model.addAttribute("totalPage",totalPage);
return "admin/courseManager"; //新增代码
}
//显示添加页面
@RequestMapping("/showAdd")
public String showAdd() {
return "admin/courseAdd";
}
//保存课程信息
@RequestMapping("/save")
public String save(TbCourse tbCourse){
//调用service保存课程信息
courseService.save(tbCourse);
return "redirect:/course/";
}
//显示编辑页面
@RequestMapping("/showModify")
public String showModify(Integer courseid,Map map) {
TbCourse tbCourse = courseService.getCourseById(courseid);
map.put("c", tbCourse);
return "admin/courseModify";
}
@RequestMapping("/modify")
public String modify(TbCourse tbCourse) {
courseService.update(tbCourse);
return "redirect:/course/";
}
@RequestMapping("/delete")
public String delete(Integer courseid) {
courseService.delete(courseid);
return "redirect:/course/";
}
}
修改 courseManager.jsp
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<%@taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%>
课程ID
课程名称
课程学时
课程学分
操作
${c.courseid }
${c.coursename }
${c.hour }
${c.score }
编辑
删除
输出：点击课程管理---进入课程管理页面--点击 》 ---进入第二页 2为总页数 10为总课程数
