JAVA - SpringBoot项目引用MyBatis操作数据库

JAVA - SpringBoot项目引用MyBatis操作数据库

1. 创建SpringBoot项目，参考：https://www.cnblogs.com/1285026182YUAN/p/12329727.html

2. 引用generator生成 Mybatis文件，参考：https://www.cnblogs.com/1285026182YUAN/p/12334401.html

 添加POM依赖：

  　　　 <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>2.1.1</version>
        </dependency>

        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>8.0.19</version>
        </dependency>

创建Service相关文件，controller相关文件。

接口文件：orderservice

package com.example.recordboot.service;

import com.example.recordboot.entity.TblOrder;

import java.util.List;

public interface OrderService {

public TblOrder GetModel();
}

服务文件：orderserviceImpl

package com.example.recordboot.service;

import com.example.recordboot.dao.TblOrderMapper;
import com.example.recordboot.entity.TblOrder;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import javax.annotation.Resource;

@Service
public class OrderServiceImpl implements OrderService {

    @Resource
    private TblOrderMapper tblOrderMapper;

    @Override
    public TblOrder GetModel() {
       TblOrder res = tblOrderMapper.selectByPrimaryKey(50);

        return  res;
    }

}

controller文件：

package com.example.recordboot.controller;

import com.example.recordboot.entity.TblOrder;
import com.example.recordboot.service.OrderService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

@RestController
@RequestMapping("/Order")
public class OrderController {

    @Autowired
    private OrderService orderService;

    @RequestMapping("/GetModel")
    public TblOrder GetModel() {
        TblOrder res = orderService.GetModel();
        return res;
    }

}

RestController是responsebody+Controller两个注解的合体，一般就拿来直接传json数据。  为什么可以直接传个对象过去呢？这是因为springboot内置了jackson模块，可以在maven的依赖下看到这方面的jar包

简单的配置与设置：

好现在讲讲设置，这里会想到，那些Controller啊，@Service啊还有MyBatis的注解@Mapper什么的spring怎么知道在哪呢？不用像mvc那样搞个扫描设置吗？

是的要的，这些我们在启动类做了简单的设置：

package com.example.recordboot;

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

@SpringBootApplication
@MapperScan(basePackages = "com.example.recordboot.dao")//这个注解注意一下 放DAO层的包名 对这个包下进行注入
public class RecordbootApplication {

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

}

application.properties 配置文件

#设置端口号
server.port=

spring.devtools.restart.enabled=true
spring.devtools.restart.additional-paths=src/main/java  

spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
spring.datasource.url=jdbc:mysql://127.0.0.1:3306/db1?useUnicode=true&characterEncoding=UTF-8&serverTimezone=Asia/Shanghai
spring.datasource.username=root
spring.datasource.password=

#mybatis配置
#首先是实体类所在的包的名字
mybatis.type-aliases-package=com.example.recordboot.entity
mybatis.mapper-locations=classpath:mapper/*.xml
#mybatis使用resources的xml来映射数据库表，这里就是resources下的mapper包的所有xml文件

dao 文件

package com.example.recordboot.dao;

import com.example.recordboot.entity.TblOrder;

public interface TblOrderMapper {
    int deleteByPrimaryKey(Integer id);

    int insert(TblOrder record);

    int insertSelective(TblOrder record);

    TblOrder selectByPrimaryKey(Integer id);

    int updateByPrimaryKeySelective(TblOrder record);

    int updateByPrimaryKey(TblOrder record);
}

entity 文件

package com.example.recordboot.entity;

import java.util.Date;

public class TblOrder {
    private Integer id;

    private String orderCode;

    private Integer userId;

    private Integer amount;

    private Date uptime;

    private String text;

    public Integer getId() {
        return id;
    }

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

    public String getOrderCode() {
        return orderCode;
    }

    public void setOrderCode(String orderCode) {
        this.orderCode = orderCode;
    }

    public Integer getUserId() {
        return userId;
    }

    public void setUserId(Integer userId) {
        this.userId = userId;
    }

    public Integer getAmount() {
        return amount;
    }

    public void setAmount(Integer amount) {
        this.amount = amount;
    }

    public Date getUptime() {
        return uptime;
    }

    public void setUptime(Date uptime) {
        this.uptime = uptime;
    }

    public String getText() {
        return text;
    }

    public void setText(String text) {
        this.text = text;
    }
}

mapper文件

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd" >
<mapper namespace="com.example.recordboot.dao.TblOrderMapper" >
  <resultMap id="BaseResultMap" type="com.example.recordboot.entity.TblOrder" >
    <id column="id" property="id" jdbcType="INTEGER" />
    <result column="order_code" property="orderCode" jdbcType="VARCHAR" />
    <result column="user_id" property="userId" jdbcType="INTEGER" />
    <result column="amount" property="amount" jdbcType="INTEGER" />
    <result column="uptime" property="uptime" jdbcType="TIMESTAMP" />
    <result column="text" property="text" jdbcType="VARCHAR" />
  </resultMap>
  <sql id="Base_Column_List" >
    id, order_code, user_id, amount, uptime, text
  </sql>
  <select id="selectByPrimaryKey" resultMap="BaseResultMap" parameterType="java.lang.Integer" >
    select
    <include refid="Base_Column_List" />
    from tbl_order
    where id = #{id,jdbcType=INTEGER}
  </select>
  <delete id="deleteByPrimaryKey" parameterType="java.lang.Integer" >
    delete from tbl_order
    where id = #{id,jdbcType=INTEGER}
  </delete>
  <insert id="insert" parameterType="com.example.recordboot.entity.TblOrder" >
    <selectKey resultType="java.lang.Integer" keyProperty="id" order="AFTER" >
      SELECT LAST_INSERT_ID()
    </selectKey>
    insert into tbl_order (order_code, user_id, amount,
      uptime, text)
    values (#{orderCode,jdbcType=VARCHAR}, #{userId,jdbcType=INTEGER}, #{amount,jdbcType=INTEGER},
      #{uptime,jdbcType=TIMESTAMP}, #{text,jdbcType=VARCHAR})
  </insert>
  <insert id="insertSelective" parameterType="com.example.recordboot.entity.TblOrder" >
    <selectKey resultType="java.lang.Integer" keyProperty="id" order="AFTER" >
      SELECT LAST_INSERT_ID()
    </selectKey>
    insert into tbl_order
    <trim prefix="(" suffix=")" suffixOverrides="," >
      <if test="orderCode != null" >
        order_code,
      </if>
      <if test="userId != null" >
        user_id,
      </if>
      <if test="amount != null" >
        amount,
      </if>
      <if test="uptime != null" >
        uptime,
      </if>
      <if test="text != null" >
        text,
      </if>
    </trim>
    <trim prefix="values (" suffix=")" suffixOverrides="," >
      <if test="orderCode != null" >
        #{orderCode,jdbcType=VARCHAR},
      </if>
      <if test="userId != null" >
        #{userId,jdbcType=INTEGER},
      </if>
      <if test="amount != null" >
        #{amount,jdbcType=INTEGER},
      </if>
      <if test="uptime != null" >
        #{uptime,jdbcType=TIMESTAMP},
      </if>
      <if test="text != null" >
        #{text,jdbcType=VARCHAR},
      </if>
    </trim>
  </insert>
  <update id="updateByPrimaryKeySelective" parameterType="com.example.recordboot.entity.TblOrder" >
    update tbl_order
    <set >
      <if test="orderCode != null" >
        order_code = #{orderCode,jdbcType=VARCHAR},
      </if>
      <if test="userId != null" >
        user_id = #{userId,jdbcType=INTEGER},
      </if>
      <if test="amount != null" >
        amount = #{amount,jdbcType=INTEGER},
      </if>
      <if test="uptime != null" >
        uptime = #{uptime,jdbcType=TIMESTAMP},
      </if>
      <if test="text != null" >
        text = #{text,jdbcType=VARCHAR},
      </if>
    </set>
    where id = #{id,jdbcType=INTEGER}
  </update>
  <update id="updateByPrimaryKey" parameterType="com.example.recordboot.entity.TblOrder" >
    update tbl_order
    set order_code = #{orderCode,jdbcType=VARCHAR},
      user_id = #{userId,jdbcType=INTEGER},
      amount = #{amount,jdbcType=INTEGER},
      uptime = #{uptime,jdbcType=TIMESTAMP},
      text = #{text,jdbcType=VARCHAR}
    where id = #{id,jdbcType=INTEGER}
  </update>
</mapper>

generatorConfig.xml 文件

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE generatorConfiguration
        PUBLIC "-//mybatis.org//DTD MyBatis Generator Configuration 1.0//EN"
        "http://mybatis.org/dtd/mybatis-generator-config_1_0.dtd">

<generatorConfiguration>
    <!--<properties resource="application.properties"/>-->
    <!--这里注释掉，后面集成插件的时候，在pom.xml文件导入驱动-->
    <!--<classPathEntry location="～/mysql/mysql-connector-java-8.0.19.jar" />-->
    <!--1，MyBatis3：默认的值；
        2，MyBatis3Simple：生成的mapper和xml比较简洁干净-->
    <context id="Mysql" targetRuntime="MyBatis3" defaultModelType="flat">
        <property name="beginningDelimiter" value="`"/>
        <property name="endingDelimiter" value="`"/>
        <property name="javaFileEncoding" value="UTF-8"/>
        <!--pressAllComments:MyBatis3默认为false，true则默认不生成注释
        suppressDate:MyBatis3默认为false，默认不生成时间戳-->
        <commentGenerator>
            <property name="suppressDate" value="true"/>
            <property name="suppressAllComments" value="true"/>
        </commentGenerator>
        <!--新版mysql驱动用的是com.mysql.cj.jdbc.Driver，老版本的是com.mysql.jdbc.Driver-->
        <jdbcConnection driverClass="com.mysql.cj.jdbc.Driver"
                        connectionURL="jdbc:mysql://127.0.0.1:3306/db1?useUnicode=true&amp;characterEncoding=UTF-8&amp;serverTimezone=UTC"
                        userId="root"
                        password="123456">
        </jdbcConnection>

        <javaModelGenerator targetPackage="com.example.recordboot.entity" targetProject="src/main/java"/>

        <sqlMapGenerator targetPackage="mapper" targetProject="src/main/resources"/>

        <javaClientGenerator targetPackage="com.example.recordboot.dao" targetProject="src/main/java" type="XMLMAPPER"/>

        <!--去掉example代码-->
        <table tableName="tbl_order" domainObjectName="TblOrder" enableCountByExample="false"
               enableUpdateByExample="false" enableDeleteByExample="false"
               enableSelectByExample="false" selectByExampleQueryId="false">
            <!--% 表示全部表-->
            <!--mysql 配置-->
            <generatedKey column="id" sqlStatement="Mysql" identity="true"/>
            <!--oracle 配置-->
            <!--  <generatedKey column="id" sqlStatement="select SEQ_{1}.nextval from dual" identity="false" type="pre"/> -->
        </table>

    </context>
</generatorConfiguration>

完成。

引用：https://www.cnblogs.com/wangshen31/p/8744157.html