Springboot集成MyBatis

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一、介绍

MyBatis 是一款优秀的持久层框架，它支持定制化 SQL、存储过程以及高级映射。MyBatis 避免了几乎所有的 JDBC 代码和手动设置参数以及获取结果集。MyBatis 可以使用简单的 XML 或注解来配置和映射原生信息，将接口和 Java 的 POJOs(Plain Old Java Objects,普通的 Java对象)映射成数据库中的记录。

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二、创建项目

使用idea创建空项目并记得选择web，mysql，mybaties这几个依赖即可，在此就不赘述了，创建后包依赖大致如下：

<dependencies>
	<dependency>
	    <groupId>org.springframework.boot</groupId>
	    <artifactId>spring-boot-starter-web</artifactId>
	</dependency>
	<dependency>
	    <groupId>org.mybatis.spring.boot</groupId>
	    <artifactId>mybatis-spring-boot-starter</artifactId>
	    <version>1.3.2</version>
	</dependency>
	
	<dependency>
	    <groupId>mysql</groupId>
	    <artifactId>mysql-connector-java</artifactId>
	    <scope>runtime</scope>
	</dependency>
	<dependency>
	    <groupId>org.springframework.boot</groupId>
	    <artifactId>spring-boot-starter-test</artifactId>
	    <scope>test</scope>
	</dependency>
</dependencies>

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三、在yml配置中添加相关配置

spring:
  datasource:
    url: jdbc:mysql://localhost:3306/test
    username: root
    password: root
    driver-class-name: com.mysql.jdbc.Driver

# 之后的填写mybatis的mapper书写路径
mybatis:
  mapper-locations: classpath:mapper/*.xml

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四、创建一个实体类

SysUserEntity.java

package cn.gausscode.calo.user.entity;
import java.util.Date;

public class SysUserEntity {
    private int id;
    private String name;
    private String loginName;
    private String email;
    private int tel;
    private String password;
    private String picUrl;
    private String siteId;
    private Date createDate;
    private int createBy;
    private Date updateDate;
    private int updateId;
    private int delFlag;
    private String remarks;

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getLoginName() {
        return loginName;
    }

    public void setLoginName(String loginName) {
        this.loginName = loginName;
    }

    public String getEmail() {
        return email;
    }

    public void setEmail(String email) {
        this.email = email;
    }

    public int getTel() {
        return tel;
    }

    public void setTel(int tel) {
        this.tel = tel;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }

    public String getPicUrl() {
        return picUrl;
    }

    public void setPicUrl(String picUrl) {
        this.picUrl = picUrl;
    }

    public String getSiteId() {
        return siteId;
    }

    public void setSiteId(String siteId) {
        this.siteId = siteId;
    }

    public Date getCreateDate() {
        return createDate;
    }

    public void setCreateDate(Date createDate) {
        this.createDate = createDate;
    }

    public int getCreateBy() {
        return createBy;
    }

    public void setCreateBy(int createBy) {
        this.createBy = createBy;
    }

    public Date getUpdateDate() {
        return updateDate;
    }

    public void setUpdateDate(Date updateDate) {
        this.updateDate = updateDate;
    }

    public int getUpdateId() {
        return updateId;
    }

    public void setUpdateId(int updateId) {
        this.updateId = updateId;
    }

    public int getDelFlag() {
        return delFlag;
    }

    public void setDelFlag(int delFlag) {
        this.delFlag = delFlag;
    }

    public String getRemarks() {
        return remarks;
    }

    public void setRemarks(String remarks) {
        this.remarks = remarks;
    }

    @Override
    public String toString() {
        return "SysUserEntity{" +
                "id=" + id +
                ", name='" + name + '\'' +
                ", loginName='" + loginName + '\'' +
                ", email='" + email + '\'' +
                ", tel=" + tel +
                ", password='" + password + '\'' +
                ", picUrl='" + picUrl + '\'' +
                ", siteId='" + siteId + '\'' +
                ", createDate=" + createDate +
                ", createBy=" + createBy +
                ", updateDate=" + updateDate +
                ", updateId=" + updateId +
                ", delFlag=" + delFlag +
                ", remarks='" + remarks + '\'' +
                '}';
    }
}

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五、创建一个dao层，service层以及controller层

SysUserDao.java

package cn.gausscode.calo.user.dao;

import cn.gausscode.calo.user.entity.SysUserEntity;
import org.apache.ibatis.annotations.Mapper;

@Mapper
public interface SysUserDao {
    SysUserEntity get(int id);

    void insert(SysUserEntity sysUserEntity);

    void delete(int id);

    void update(SysUserEntity sysUserEntity);
}

SysUserController.java

package cn.gausscode.calo.user.controller;

import cn.gausscode.calo.user.service.SysUserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

@RestController
public class SysUserController {

    @Autowired
    SysUserService sysUserService;

    @RequestMapping("/get")
    public String get(){
        int id = 2;
        return sysUserService.get(id);
    }

    @RequestMapping("/insert")
    public String insert(){
        return sysUserService.insert().toString();
    }

    @RequestMapping("/delete")
    public String delete(){
        sysUserService.delete();
        return "successful delete";
    }

    @RequestMapping("/update")
    public String update(){
        return sysUserService.update();
    }

}

SysUserService.java

package cn.gausscode.calo.user.service;

import cn.gausscode.calo.user.dao.SysUserDao;
import cn.gausscode.calo.user.entity.SysUserEntity;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.text.SimpleDateFormat;
import java.util.Date;

@Service
public class SysUserService {

    @Autowired
    SysUserDao sysUserDao;

    public String get(int id){
        return sysUserDao.get(id).toString();
    }

    public SysUserEntity insert(){
        SysUserEntity sysUserEntity = new SysUserEntity();
        sysUserEntity.setName("name");
        sysUserEntity.setLoginName("loginName");
        sysUserEntity.setEmail("email");
        sysUserEntity.setTel(123);
        sysUserEntity.setPassword("password");
        sysUserEntity.setPicUrl("pic_url");
        sysUserEntity.setSiteId("site_id");
        SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        sysUserEntity.setCreateDate(new Date());
        sysUserEntity.setCreateBy(1);
        sysUserEntity.setDelFlag(1);
        sysUserEntity.setRemarks("remarks");
        sysUserDao.insert(sysUserEntity);
        return sysUserEntity;

    }

    public void delete(){
        sysUserDao.delete(1);
    }

    public String update(){
        SysUserEntity sysUserEntity = new SysUserEntity();
        sysUserEntity.setId(1);
        sysUserEntity.setName("name1");
        sysUserEntity.setLoginName("loginName1");
        sysUserEntity.setEmail("email1");
        sysUserEntity.setTel(1231);
        sysUserEntity.setPassword("password1");
        sysUserEntity.setPicUrl("pic_url1");
        sysUserEntity.setSiteId("site_id1");
        SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss1");
        sysUserEntity.setCreateDate(new Date());
        sysUserEntity.setCreateBy(11);
        sysUserEntity.setDelFlag(11);
        sysUserEntity.setRemarks("remarks1");
        sysUserDao.update(sysUserEntity);
        return sysUserDao.get(1).toString();
    }
}

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六、书写mybatis的mapper

SysUserMapper.xml

<!DOCTYPE mapper
        PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">

<mapper namespace="cn.gausscode.calo.user.dao.SysUserDao">

    <select id="get" parameterType="int" resultType="cn.gausscode.calo.user.entity.SysUserEntity">
        select * from sys_user where id = #{id}
    </select>

    <insert id="insert" parameterType="cn.gausscode.calo.user.entity.SysUserEntity">
        insert into sys_user (name,login_name,email,tel,password,pic_url,site_id,create_date,create_by,update_date,update_by,del_flag,remarks)
                values (#{name},#{loginName},#{email},#{tel},#{password},#{picUrl},#{siteId},#{createDate},#{createBy},#{updateDate},#{updateId},#{delFlag},#{remarks})
    </insert>

    <update id="delete" parameterType="int">
        update sys_user set del_flag = 0 where id = #{id}
    </update>

    <update id="update" parameterType="cn.gausscode.calo.user.entity.SysUserEntity">
        update sys_user set
            name = #{name},
            login_name = #{loginName},
            email = #{email},
            tel = #{tel},
            password = #{password},
            pic_url = #{picUrl},
            site_id = #{siteId},
            create_date = #{createDate},
            create_by = #{createBy},
            update_date = #{updateDate},
            update_by = #{updateId},
            del_flag = #{delFlag},
            remarks = #{remarks}
        where id = #{id}
    </update>
</mapper>

至此增删改查功能就完成了

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七、总结

下面这个是整个项目的结构图

整体来说，mybatis可以大量减少了在sql代码部分的心思，特别是动态sql部分，简直太棒了，不过还没有完全学完，只是今天写了一个demo，之后会慢慢地把整个mybatis系统的学习总结一下