基于SpringBoot的Mybatis-Plus插件整合

公司刚开发一个ssm架构的项目，同事推荐了mybatis的一个插件，发现上手容易，高效简洁。下面是官方的文档： 传送门请进

我的demo目录：注意SpringBoot的启动类的位置

1.首先添加pom文件的依赖：

        <dependency>
            <groupId>com.baomidougroupId>
            <artifactId>mybatisplus-spring-
            boot-starterartifactId>
            <version>1.0.4version>
        dependency>

        <dependency>
            <groupId>com.baomidougroupId>
            <artifactId>mybatis-plusartifactId>
            <version>2.0.7version>
        dependency>

注意： mybatis-plus 自动的维护了mybatis以及mybatis-spring的依赖，在springboot中这三者不能同时的出现，避免版本的冲突，表示：跳进过这个坑。。。

2、application.properties 文件；

#tomcat\u7F16\u7801
server.port=8081

# salt used for generate token
token-random-salt=restyle@123

# \u6570\u636E\u6E90\u914D\u7F6E
spring.datasource.type=com.alibaba.druid.pool.DruidDataSource
spring.datasource.driver-class-name=com.mysql.jdbc.Driver
spring.datasource.url=jdbc:mysql://localhost:3306/db_stu_crm?useUnicode=true&characterEncoding=utf8&useSSL=false
spring.datasource.username=root
spring.datasource.password=root
spring.datasource.initialSize=5
spring.datasource.minIdle=5
spring.datasource.maxActive=20
spring.datasource.maxWait=60000
spring.datasource.timeBetweenEvictionRunsMillis=60000
spring.datasource.minEvictableIdleTimeMillis=300000
spring.datasource.validationQuery=SELECT 1 FROM DUAL
spring.datasource.testWhileIdle=true
spring.datasource.testOnBorrow=false
spring.datasource.testOnReturn=false
spring.datasource.poolPreparedStatements=true
spring.datasource.maxPoolPreparedStatementPerConnectionSize=20
spring.datasource.filters=stat,wall,log4j
spring.datasource.connectionProperties=druid.stat.mergeSql=true;druid.stat.slowSqlMillis=5000


mybatis-plus.mapper-locations=classpath:/mapper/*Mapper.xml
mybatis-plus.typeAliasesPackage=com.cn.restyle.entity

数据源的配置：

package com.cn.restyle.config;

import javax.sql.DataSource;

import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.jdbc.datasource.DataSourceTransactionManager;

import com.alibaba.druid.pool.DruidDataSource;

/**
 * 数据源配置
 */
@Configuration
public class DataSourceConfig {

    @Bean(name="dataSource")
    @ConfigurationProperties(prefix="spring.datasource")
    public DataSource dataSource(){
        return new DruidDataSource();
    } 

    // 配置事物管理器
    @Bean(name="transactionManager") 
    public DataSourceTransactionManager transactionManager(){
        return new DataSourceTransactionManager(dataSource());
    }

}

3、mybatis的配置

package com.cn.restyle.config;

import org.mybatis.spring.annotation.MapperScan;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

import com.baomidou.mybatisplus.plugins.PaginationInterceptor;

@Configuration
//扫描dao或者是Mapper接口
@MapperScan("com.cn.restyle.mapper*")
public class MybatisPlusConfig {
    /**
     * mybatis-plus 分页插件
     */

    @Bean
    public PaginationInterceptor paginationInterceptor(){
        PaginationInterceptor page = new PaginationInterceptor();
        page.setDialectType("mysql");
        return page;
    }

}

4、 新建一个Student 的表

package com.cn.restyle.entity;

import java.util.Date;


import com.baomidou.mybatisplus.annotations.TableField;
import com.baomidou.mybatisplus.annotations.TableId;
import com.baomidou.mybatisplus.annotations.TableName;
import com.baomidou.mybatisplus.enums.IdType;
import com.fasterxml.jackson.annotation.JsonFormat;

@TableName("tb_student")
public class Student {

    @TableId(value="id",type=IdType.AUTO)
    private Integer id;

    @TableField("stu_name")
    private String stuName;

    @TableField("stu_number")
    private String stuNumber;

    private Integer gender;
    private Integer age;

    private String password;

    @TableField("stu_mobile")
    private String stuMobile;

    /**
     * 家长姓名
     */ 
    @TableField("par_name")
    private String parName;

    @TableField("par_mobile")
    private String parMobile;

    @JsonFormat(pattern="yyyy-MM-dd HH:mm:ss")
    @TableField("create_time")
    private Date createTime;

    @TableField("is_delete")
    private Integer isDelete;

    @TableField("role_id")
    private Integer roleId;



    // setter和getter方法省略


}

注意： 在这儿注解： @TableName（“tb_student”）,它是指与数据库的关联，意味着表对应的数据库的表名是tb_student.
再者，另一个注解，@TableFile（exist=false），表示Student类中有的属性，而对应的属性在表中没有这样的一个字段

5、 新建dao层接口StudentMapper：

package com.cn.restyle.mapper;

import java.util.List;

import org.apache.ibatis.annotations.Select;
import org.springframework.stereotype.Repository;

import com.baomidou.mybatisplus.mapper.BaseMapper;
import com.baomidou.mybatisplus.plugins.Page;
import com.baomidou.mybatisplus.plugins.pagination.Pagination;
import com.cn.restyle.entity.Student;
/**
* Student 表数据层控制接口
*/

@Repository
public interface StudentMapper extends BaseMapper {

    List findAllStudent();

    List findSomeColumn();

    void deleteById(Integer id);

    void updateByPrimarKeySelective(Student student);

    void saveStudent(Student student);

    List findAllStudentPage(Pagination page);


    @Select("select * from tb_student where gender = #{gender}")
    @Results({
        @Result(column="stu_name",property="stuName"),
        @Result(column="stu_mobile",property="stuMobile"),
        @Result(column="stu_number",property="stuNumber"),
        @Result(column="par_name",property="parName"),
        @Result(column="par_mobile",property="parMobile"),
        @Result(column="create_time",property="createTime")
    })
    List findStuByGender(Integer gender);



}

注意 ： 如果在xml 中不写SQL的，可以使用注解的方式在此接口当中直接写SQL，实体和数据库表字段不一致，使用@Result注解来映射

6、 新建StudentMapper的配置文件：

<mapper namespace="com.cn.restyle.mapper.StudentMapper">
    <resultMap id="BaseResultMap" type="com.cn.restyle.entity.Student">
        <id column="id" property="id">id>
        <result column="stu_name" property="stuName">result>
        <result column="stu_mobile" property="stuMobile">result>
        <result column="stu_number" property="stuNumber">result>
        <result column="create_time" property="createTime">result>
        <result column="role_id" property="roleId">result>
        <result column="par_mobile" property="parMobile">result>
        <result column="par_name" property="parName">result>
        <result column="is_delete" property="isDelete">result>
    resultMap>

    <sql id="base_column_list">
        stu_name,stu_mobile,stu_number,create_time,par_mobile,par_name
    sql>

    <insert id="insertStudent" parameterType="com.cn.restyle.entity.Student">
        insert into tb_student (stu_name,stu_mobile,stu_number,par_mobile,par_name)
        values
        (#{stuName},#{stuMobile},#{stuNumber},#{parMobile},#{parName})
    insert>


    <insert id="saveStudent" parameterType="com.cn.restyle.entity.Student">
        insert into tb_student
        <trim prefix="(" suffix=")" suffixOverrides="," >
            <if test="stuName != null">
                stu_name,
            if>
            <if test="stuMobile">
                stu_mobile,
            if>
            <if test="stuNumber">
            stu_number,
            if>
            <if test="roleId">
            role_id,
            if>
            <if test="parMobile">
            par_mobile,
            if>
            <if test="parName">
            par_name,
            if>
        trim>
        <trim prefix="values (" suffix=")" suffixOverrides=",">
        <if test="stuName != null">#{stuName},if>
        <if test="stuMobile != null">#{stuMobile},if>
        <if test="stuNumber!= null">#{stuNumber},if>
        <if test="roleId !=null">#{roleId},if>
        <if test="parMobile != null">#{parMobile},if>
        <if test="parName !=null">#{parName},if>
        trim>
    insert>

    <delete id="deleteById" parameterType="java.lang.Integer">
        delete from tb_student
        where id = #{id}
    delete>

    <update id="updateByPrimarKeySelective" parameterType="com.cn.restyle.entity.Student">
        update tb_student
        <set>
            <if test="stuName ! = null">
                stu_name = #{stuName}
            if>
            <if test="password ! =null">
                password = #{password}
            if>
            <if test="stuMobile ! = null">
                stu_mobile = #{stuMobile}
            if>
        set>
    update>

    <update id="updateByprimaryKey">
    update tb_student
    set
    stu_name = #{stuName}
    password = #{password}
    stu_mobile = #{stuMobile}

    update>

    <select id="findSomeColumn" resultMap="BaseResultMap">
        select
        <include refid="base_column_list" />
        from tb_student
    select>

    <select id="findAllStudent" resultMap="BaseResultMap">
        select * from tb_student
    select>

    <select id="findAllStudentPage" resultMap="BaseResultMap" resultType="Student">
        select * from tb_student
    select>


mapper>

7、新建service层的类StudentService ：

package com.cn.restyle.services;

import java.util.List;

import com.baomidou.mybatisplus.plugins.Page;
import com.baomidou.mybatisplus.plugins.pagination.Pagination;
import com.baomidou.mybatisplus.service.IService;
import com.cn.restyle.entity.Student;

public interface StudentService extends IService {

    List findAllStudent();
    List findSomeColumn();

    void deleteById(Integer id);

    void updateByPrimarKeySelective(Student student);

    void saveStudent(Student student);

    Page findAllStudentPage(Page page);

    List findStuByGender(Integer gender);

}

8、service的实现类：

package com.cn.restyle.services.impl;



import java.util.List;

import org.springframework.stereotype.Service;

import com.baomidou.mybatisplus.plugins.Page;
import com.baomidou.mybatisplus.plugins.pagination.Pagination;
import com.baomidou.mybatisplus.service.impl.ServiceImpl;
import com.baomidou.mybatisplus.toolkit.PackageHelper;
import com.cn.restyle.entity.Student;
import com.cn.restyle.mapper.StudentMapper;
import com.cn.restyle.services.StudentService;

@Service
public class StudentServiceImpl extends ServiceImpl 
                                implements StudentService {

    @Override
    public List findAllStudent() {
        // TODO Auto-generated method stub
        return baseMapper.findAllStudent();
    }

    @Override
    public List findSomeColumn() {
        // TODO Auto-generated method stub
        return baseMapper.findSomeColumn();
    }

    @Override
    public void deleteById(Integer id) {
        baseMapper.deleteById(id);

    }

    @Override
    public void updateByPrimarKeySelective(Student student) {
        baseMapper.updateById(student);

    }

    @Override
    public void saveStudent(Student student) {
        baseMapper.saveStudent(student);

    }

    @Override
    public Page findAllStudentPage(Page page) {
        // TODO Auto-generated method stub
        page.setRecords(baseMapper.findAllStudentPage(page));
        return page;
    }

    @Override
    public List findStuByGender(Integer gender) {
        // TODO Auto-generated method stub
        return baseMapper.findStuByGender(gender);
    }


}

测试的Controller：

package com.cn.restyle.controller;

import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;

import com.baomidou.mybatisplus.mapper.EntityWrapper;
import com.baomidou.mybatisplus.plugins.Page;
import com.cn.restyle.entity.Student;
import com.cn.restyle.services.StudentService;
import com.cn.restyle.util.Result;

import lombok.extern.slf4j.Slf4j;

@RestController
@RequestMapping("/v1/login")
@Slf4j
public class TestController {

    @Autowired
    private StudentService studentService;

    @RequestMapping("/register")
    public Result Register(@RequestBody Student student){
        studentService.insert(student);
        return new Result(Result.OK,"保存成功");
    }

    @RequestMapping("/findAllStudent")
    public Result test1(){
        Result result = new Result();
        List student = studentService.findAllStudent();
        result.setData(student);
        return result;
    }

    @RequestMapping("findSomeColumn")
    public Result test2(){
        Result result = new Result();
        List stu = studentService.findSomeColumn();
        result.setData(stu);
        return result;
    }

    @RequestMapping("deleteById/{id}")
    public Result test3(@PathVariable  Integer id){
        Result result = new Result();
        studentService.deleteById(id);
        result.setMsg("删除成功");
        return result;
    }

    @RequestMapping("updateByPrimarKeySelective")
    public Result test4(@RequestBody Student student){
        Result result = new Result();
        EntityWrapper entityWrapper = new EntityWrapper<>();
        entityWrapper.eq("stu_mobile", student.getStuMobile());
        Student stu = studentService.selectOne(entityWrapper);
        if (null != stu) {
            stu.setParName("my hero");
            stu.setStuName("zxs");
        }
        studentService.updateByPrimarKeySelective(stu);
        result.setData(stu);
        return result;
    }

    @RequestMapping("/saveStudent")
    public Result test5(@RequestBody Student student){
        Result result = new Result();
        studentService.saveStudent(student);
        result.setData(student);

        return result;

    }
    /**
     * 分页的方法
     * @param pageNumber
     * @param pageSize
     * @return
     */
    @RequestMapping("page/{pageNumber}")
    public Result findAllStuPage(@PathVariable Integer pageNumber,
                                     @RequestParam(defaultValue="6") Integer pageSize){
        Result result = new Result();
        Page page = new Page(pageNumber,pageSize);
        Page pageStu = studentService.findAllStudentPage(page);
         result.setData(pageStu.getRecords());
        return result;

    }

    @RequestMapping("pageByGender/{pageNumber}")
    public Result findStuByGender(@PathVariable Integer pageNumber,
            @RequestParam(defaultValue="6") Integer pageSize){
        Result result = new Result<>();

        EntityWrapper wrapper = new EntityWrapper<>();
        wrapper.eq("gender", 1);
        Page page = getPage(pageNumber, pageSize);
        Page stuPage = studentService.selectPage(page, wrapper);
        result.setData(stuPage.getRecords());

        return result;
    }



    /**
     * 获取分页对象
     * 每页显示数量
     */

    private  Page getPage(int pageNum,int pageSize){

        return new Page(pageNum,pageSize);
    }


}

SpringBoot的启动类:

package com.cn.restyle;

import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@MapperScan("com.cn.restyle.mapper")  //配置mapper扫描
@SpringBootApplication
public class CrmApplication {

    public static void main(String[] args) {
        SpringApplication.run(CrmApplication.class, args);
    }
}

另外，对于EntityWrapper的条件拼接，基本可以实现SQL中常用的where，and，or，groupby, orderby等语法

@Test
    public void testSql(String str){
        EntityWrapper wrapper = new EntityWrapper<>();
        wrapper.eq("stu_name", str)
               .or()
               .eq("par_name", str)
               .orderBy("create_time", false)   // 时间的倒叙排列
               .limit(0, 1);                    // 取一条
        Student stu = studentService.selectOne(wrapper);
    }

附：
我的Result 工具类

package com.cn.restyle.util;

public class Result {
    public static final Integer OK = 0;
    public static final Integer Error = -1;

    private Integer code;
    private String msg;
    private T data;

    public Result(){
        this.code = OK;
        this.msg = "success";
    }

    public Result(Integer code, String msg) {
        super();
        this.code = code;
        this.msg = msg;
    }

    public Result(String msg, T data) {
        super();
        this.msg = msg;
        this.data = data;
    }

    public Result(Integer code, String msg, T data) {
        super();
        this.code = code;
        this.msg = msg;
        this.data = data;
    }

    public Integer getCode() {
        return code;
    }

    public void setCode(Integer code) {
        this.code = code;
    }

    public String getMsg() {
        return msg;
    }

    public void setMsg(String msg) {
        this.msg = msg;
    }

    public T getData() {
        return data;
    }

    public void setData(T data) {
        this.data = data;
    }




}

参考文档：

mybatis-plus官方文档