SpringBoot13：整合MyBatis

整合MyBatis

官方文档：http://mybatis.org/spring-boot-starter/mybatis-spring-boot-autoconfigure/

Maven仓库地址：https://mvnrepository.com/artifact/org.mybatis.spring.boot/mybatis-spring-boot-starter/2.1.1

github官方文档：https://github.com/mybatis/spring-boot-starter/blob/master/mybatis-spring-boot-autoconfigure/src/site/markdown/index.md

整合测试

1、导入 MyBatis 所需要的依赖

<dependency>
    <groupId>org.mybatis.spring.boot</groupId>
    <artifactId>mybatis-spring-boot-starter</artifactId>
    <version>2.2.0</version>
</dependency>

2、配置数据库连接信息（这里使用的的是druid的数据源，druid的配置请回顾 SpringBoot12：整合Druid）

spring:
  datasource:
    username: root
    password: 123456
    url: jdbc:mysql://139.224.1.140:3306/mybatis?useUnicode=true&characterEncoding=utf8&useSSL=false
    driver-class-name: com.mysql.cj.jdbc.Driver
    type: com.alibaba.druid.pool.DruidDataSource # 自定义数据源

    #Spring Boot 默认是不注入这些属性值的，需要自己绑定
    #druid 数据源专有配置
    initialSize: 5
    minIdle: 5
    maxActive: 20
    maxWait: 60000
    timeBetweenEvictionRunsMillis: 60000
    minEvictableIdleTimeMillis: 300000
    validationQuery: SELECT 1 FROM DUAL
    testWhileIdle: true
    testOnBorrow: false
    testOnReturn: false
    poolPreparedStatements: true
    #配置监控统计拦截的filters，stat:监控统计、log4j：日志记录、wall：防御sql注入
    #如果允许时报错  java.lang.ClassNotFoundException: org.apache.log4j.Priority
    #则导入 log4j 依赖即可，Maven 地址：https://mvnrepository.com/artifact/log4j/log4j
    filters: stat,wall,log4j
    maxPoolPreparedStatementPerConnectionSize: 20
    useGlobalDataSourceStat: true
    connectionProperties: druid.stat.mergeSql=true;druid.stat.slowSqlMillis=500

#mybatis配置
mybatis:
  type-aliases-package: com.edgar.pojo
  mapper-locations: classpath:mybatis/mapper/*.xml

3、测试数据库是否连接成功！

package com.edgar;

import com.alibaba.druid.pool.DruidDataSource;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;

import javax.sql.DataSource;
import java.sql.Connection;
import java.sql.SQLException;

@SpringBootTest
class Springboot05MybatisApplicationTests {
    @Autowired
    DataSource dataSource;

    @Test
    void contextLoads() throws SQLException {

        //看一下默认数据源
        System.out.println(dataSource.getClass());
        //获得连接
        Connection connection =   dataSource.getConnection();
        System.out.println(connection);

        DruidDataSource druidDataSource = (DruidDataSource) dataSource;
        System.out.println("druidDataSource 数据源最大连接数：" + druidDataSource.getMaxActive());
        System.out.println("druidDataSource 数据源初始化连接数：" + druidDataSource.getInitialSize());

        //关闭连接
        connection.close();
    }

}

4、创建实体类

User.java

package com.edgar.pojo;

import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;

@Data
@AllArgsConstructor
@NoArgsConstructor
public class User {

    private int id;
    private String name;
    private String pwd;
}

5、创建mapper目录以及对应的 Mapper 接口

UserMapper.java

package com.edgar.mapper;

import com.edgar.pojo.User;
import org.apache.ibatis.annotations.Mapper;

import java.util.List;


//@Mapper : 表示本类是一个 MyBatis 的 Mapper
@Mapper
public interface UserMapper {

    List<User> queryUserList();

    User queryUserById(int id);

    int addUser(User user);

    int updateUser(User user);

    int deleteUser(int id);


}

6、对应的Mapper映射文件

路径：src/main/resources/mybatis/mapper/UserMapper.xml

UserMapper.xml

<?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.edgar.mapper.UserMapper">

    <select id="queryUserList" resultType="User">
        select * from mybatis.user;
    </select>

    <select id="queryUserById" resultType="User" parameterType="int">
        select * from mybatis.user where id = #{id};
    </select>

    <insert id="addUser" parameterType="User">
        insert into mybatis.user(id, name, pwd) VALUES (#{id},#{name},#{pwd})
    </insert>

    <update id="updateUser" parameterType="User">
        update mybatis.user set name=#{name},pwd=#{pwd} where id=#{id}
    </update>

    <delete id="deleteUser" parameterType="int">
        delete from mybatis.user where id=#{id}
    </delete>
</mapper>

8、编写 UserController 进行测试！

package com.edgar.controller;

import com.edgar.mapper.UserMapper;
import com.edgar.pojo.User;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;

import java.util.List;

@RestController
public class UserController {

    @Autowired
    UserMapper userMapper;

    @GetMapping("/queryUserList")
    public List<User> queryUserList(){
        List<User> userList = userMapper.queryUserList();
        return userList;
    }

    @GetMapping("/addUser")
    public String addUser(){
        userMapper.addUser(new User(7,"小毛","333333"));
        return "OK";
    }

    @GetMapping("/updateUser")
    public String updateUser(){
        userMapper.updateUser(new User(7,"小毛","4444444"));
        return "Ok";
    }

    @GetMapping("/deleteUser")
    public String deleteUser(){
        userMapper.deleteUser(7);
        return "OK";
    }


}

启动项目访问进行测试！