springboot整合mybatis

您所在的位置：网站首页 › mybits plus入门 › springboot整合mybatis

springboot整合mybatis

2024-07-07 09:36:27| 来源: 网络整理| 查看: 265

1.mybatis-plus，plus意思为插件，只在原来的基础上增强不做改变，只要进行简单的配置就可以对单表进行crud,还提供了强大的条件构造器wrapper以及代码生成器等。如下为springboot整合mybatis-plus3.x的小案例,项目github地址：https://github.com/baisul/springbootmybatisplusDemo.git,如下只是小案例，如果想对代码生成器，条件构造器还有其他方面进行更深入的学习，可以到mybatis-plus的官方文档学习https://baomidou.com/guide/

2.要准备的sql语句用来建表

create table student( id int(11) primary key auto_increment, sname varchar(36) default null comment'姓名', sno varchar(100) default null comment'学号', sex tinyint(2) default null comment'性别,0男，1女', hobby varchar(100) default null comment'爱好', email varchar(100) default null comment'邮箱' ) insert into student values(null,'小明','10001',0,'打篮球','[email protected]'); insert into student values(null,'小红','10002',1,'打羽毛球','[email protected]'); insert into student values(null,'小白','10003',0,'打篮球','[email protected]'); insert into student values(null,'小黑','10004',0,'打保龄球','[email protected]'); insert into student values(null,'小胖','10005',0,'打乒乓球','[email protected]'); insert into student values(null,'小新','10001',1,'打高尔夫球','[email protected]'); create table teacher( id int(11) primary key auto_increment, tname varchar(36) default null comment'姓名', tno varchar(100) default null comment'工号', sex tinyint(2) default null comment'性别', cource varchar(36) default null comment'教的课程' ) insert into teacher values(null,'李小刚','t001',0,'体育'); insert into teacher values(null,'王春心','t002',1,'语文'); insert into teacher values(null,'李明','t003',0,'数学'); insert into teacher values(null,'小黑','t004',0,'物理');

3.新建一个工程，添加依赖在这里插入图片描述 pomp.xml

4.0.0 org.springframework.boot spring-boot-starter-parent 2.3.5.RELEASE com.yl demo 0.0.1-SNAPSHOT demo Demo project for Spring Boot 1.8 org.springframework.boot spring-boot-starter-jdbc org.springframework.boot spring-boot-starter-web mysql mysql-connector-java runtime com.baomidou mybatis-plus-boot-starter 3.3.2 com.baomidou mybatis-plus-generator 3.3.2 org.apache.velocity velocity-engine-core 2.2 org.freemarker freemarker 2.3.30 org.projectlombok lombok 1.18.12 provided org.springframework.boot spring-boot-starter-test test org.junit.vintage junit-vintage-engine org.springframework.boot spring-boot-maven-plugin

4.用代码生成相关的实体类，以及mapper,service等，这里用的代码生成器有点问题，id居然没有生成在实体类里，本人手动添加的，关于mybatis-plus代码生成器的更多详细配置可以从这官方文档看https://baomidou.com/config/generator-config.html 1）项目的结构在这里插入图片描述 2）entity

package com.yl.demo.entity; import java.io.Serializable; import com.baomidou.mybatisplus.annotation.IdType; import com.baomidou.mybatisplus.annotation.TableField; import com.baomidou.mybatisplus.annotation.TableId; import lombok.Data; import lombok.EqualsAndHashCode; /** *

* *

* * @author wfj * @since 2020-11-12 */ @Data @EqualsAndHashCode(callSuper = false) public class Student implements Serializable { private static final long serialVersionUID=1L; /** * id */ @TableId(value="id",type= IdType.AUTO) private Integer id; /** * 姓名 */ private String sname; /** * 学号 */ private String sno; /** * 性别,0男，1女 */ private Integer sex; /** * 爱好 */ private String hobby; /** * 邮箱 */ private String email; } package com.yl.demo.entity; import java.io.Serializable; import com.baomidou.mybatisplus.annotation.IdType; import com.baomidou.mybatisplus.annotation.TableField; import com.baomidou.mybatisplus.annotation.TableId; import lombok.Data; import lombok.EqualsAndHashCode; /** *

* *

* * @author wfj * @since 2020-11-12 */ @Data @EqualsAndHashCode(callSuper = false) public class Teacher implements Serializable { private static final long serialVersionUID=1L; /** * id */ @TableId(value="id",type= IdType.AUTO) private Integer id; /** * 姓名 */ private String tname; /** * 工号 */ private String tno; /** * 性别 */ private Integer sex; /** * 教的课程 */ private String cource; }

3）service

package com.yl.demo.service; import com.yl.demo.entity.Student; import com.baomidou.mybatisplus.extension.service.IService; import java.util.List; /** *

* 服务类 *

* * @author wfj * @since 2020-11-12 */ public interface IStudentService extends IService { /** * 获取学生列表 * @return */ List listStudent(); /** * 根据学生ID查找学生 * @param id * @return */ Student getStudentById(Integer id); } package com.yl.demo.service; import com.yl.demo.entity.Teacher; import com.baomidou.mybatisplus.extension.service.IService; import java.util.List; /** *

* 服务类 *

* * @author wfj * @since 2020-11-12 */ public interface ITeacherService extends IService { /** * 新增一名老师 * @param teacher * @return */ Integer addTeacher(Teacher teacher); /** * 获取所有女老师信息 * @return */ List getTeacherList(); }

4）service.impl

package com.yl.demo.service.impl; import com.baomidou.mybatisplus.core.conditions.Wrapper; import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper; import com.yl.demo.entity.Student; import com.yl.demo.mapper.StudentMapper; import com.yl.demo.service.IStudentService; import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Service; import javax.annotation.Resource; import java.util.List; /** *

* 服务实现类 *

* * @author wfj * @since 2020-11-12 */ @Service public class StudentServiceImpl extends ServiceImpl implements IStudentService { @Resource private StudentMapper studentMapper; /** * 这里调的是BaseMapper里的方法，List selectList(@Param("ew") Wrapper queryWrapper); * @return */ @Override public List listStudent() { return this.studentMapper.selectList(new QueryWrapper()); } /** * 这里调的是ServiceImpl里面的方法, * @param id * @return */ @Override public Student getStudentById(Integer id) { return this.getById(id); } } package com.yl.demo.service.impl; import com.baomidou.mybatisplus.core.conditions.Wrapper; import com.baomidou.mybatisplus.core.conditions.query.LambdaQueryWrapper; import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper; import com.baomidou.mybatisplus.extension.conditions.query.QueryChainWrapper; import com.yl.demo.entity.Teacher; import com.yl.demo.mapper.TeacherMapper; import com.yl.demo.service.ITeacherService; import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl; import org.springframework.stereotype.Service; import java.util.List; /** *

* 服务实现类 *

* * @author wfj * @since 2020-11-12 */ @Service public class TeacherServiceImpl extends ServiceImpl implements ITeacherService { @Override public Integer addTeacher(Teacher teacher) { //调用ServiceImpl里的save方法，即可保存一个实体 return this.save(teacher) == true ? 1 : 0; } @Override public List getTeacherList() { //新建一个条件构造器，这个条件构造器就相当于在where后面拼接条件了 QueryWrapper wrapper = new QueryWrapper(); //设置查询条件字段sex=1的，eq等于，lt小于，gt大于，还有很多可以到官网查看 wrapper.eq("sex",1); List list = this.list(wrapper); return list; } }

5）util

package com.yl.demo.util; import com.baomidou.mybatisplus.extension.api.R; import lombok.Data; import java.io.Serializable; /** * 通用结果返回类 */ @Data public class Result implements Serializable { public int code; public String msg; public Object data; public static Result success() { Result result = new Result(); result.setCode(200); result.setMsg("操作成功"); return result; } public static Result success(int code,String msg) { Result result = new Result(); result.setCode(code); result.setMsg(msg); return result; } public static Result success(int code,String msg,Object data) { Result result = new Result(); result.setCode(code); result.setMsg(msg); result.setData(data); return result; } public static Result success(Object data) { Result result = new Result(); result.setCode(200); result.setMsg("操作成功"); result.setData(data); return result; } public static Result fail() { Result result = new Result(); result.setCode(0); result.setMsg("操作失败"); return result; } public static Result fail(int code,String msg) { Result result = new Result(); result.setCode(code); result.setMsg(msg); return result; } public static Result fail(int code,String msg,Object data) { Result result = new Result(); result.setCode(code); result.setMsg(msg); result.setData(data); return result; } }

6）controller

package com.yl.demo.controller; import com.yl.demo.entity.Student; import com.yl.demo.service.IStudentService; import com.yl.demo.util.Result; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.web.bind.annotation.GetMapping; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RequestParam; import org.springframework.web.bind.annotation.RestController; import java.util.List; /** *

* 前端控制器 *

* * @author wfj * @since 2020-11-12 */ @RestController @RequestMapping("/student") public class StudentController { @Autowired private IStudentService studentService; /** * 获取学生列表 * @return */ @GetMapping("/listStudent") public Result listStudent() { List students = studentService.listStudent(); if (students != null) { return Result.success(students); } else { return Result.fail(); } } /** * 根据学生ID获取学生 * @param id * @return */ @GetMapping("/getStudentById") public Result getStudentById(@RequestParam Integer id) { Student student = studentService.getStudentById(id); if (student != null) { return Result.success(student); } else { return Result.fail(); } } } package com.yl.demo.controller; import com.yl.demo.entity.Teacher; import com.yl.demo.service.ITeacherService; import com.yl.demo.util.Result; import org.springframework.web.bind.annotation.*; import javax.annotation.Resource; import java.util.List; /** *

* 前端控制器 *

* * @author wfj * @since 2020-11-12 */ @RestController @RequestMapping("/teacher") public class TeacherController { @Resource private ITeacherService teacherService; /** * 添加老师 * @param teacher * @return */ @PostMapping("/addTeacher") public Result addTeacher(@RequestBody Teacher teacher) { Integer result = teacherService.addTeacher(teacher); if (result > 0) { return Result.success(); } else { return Result.fail(); } } @GetMapping("/listFemaleTeacher") public Result listFemaleTeacher() { List teacherList = teacherService.getTeacherList(); if (teacherList != null) { return Result.success(teacherList); } else { return Result.fail(); } } }

7）mapper

package com.yl.demo.mapper; import com.yl.demo.entity.Student; import com.baomidou.mybatisplus.core.mapper.BaseMapper; /** *

* Mapper 接口 *

* * @author wfj * @since 2020-11-12 */ public interface StudentMapper extends BaseMapper { } package com.yl.demo.mapper; import com.yl.demo.entity.Teacher; import com.baomidou.mybatisplus.core.mapper.BaseMapper; /** *

* Mapper 接口 *

* * @author wfj * @since 2020-11-12 */ public interface TeacherMapper extends BaseMapper { }

8）mapper的xml文件

9 )application文件

spring.application.name= #配置端口号以及访问路径 server.port=8080 server.servlet.context-path=/demo #数据源 spring.datasource.url=jdbc:mysql://127.0.0.1:3306/demo?useUnicode=true&characterEncoding=utf8&useSSL=false&allowPublicKeyRetrieval=true&serverTimezone=Asia/Shanghai spring.datasource.username=root spring.datasource.password=root spring.datasource.driver-class-name=com.mysql.jdbc.Driver #mybatisplus配置 #开启驼峰命名法 mybatis-plus.configuration.map-underscore-to-camel-case=true #扫描xml文件 mybatis-plus.mapper-locations=classpath:mapper/*.xml

10 )springboot主程序在这里插入图片描述 5.用postman来进行接口测试 1)获取学生列表 2）根据学生id获取学生信息 3）添加老师这里要设置请求头，contentype为application/json