SpringBoot整合MyBatis

环境搭建

创建工程&引入坐标

1、创建一个SpringBoot工程，勾选模块web、Mysql、JDBC、MyBatis。


Spring会自动导入下面的坐标：

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

配置数据源相关属性Druid

1、引入坐标：

<!-- https://mvnrepository.com/artifact/com.alibaba/druid -->
<dependency>
    <groupId>com.alibaba</groupId>
    <artifactId>druid</artifactId>
    <version>1.1.21</version>
</dependency>

	<dependency>
		    <groupId>log4j</groupId>
		    <artifactId>log4j</artifactId>
		    <version>1.2.17</version>
		</dependency>

2、配置druid
springboot_mybatis\src\main\resources\application.yml

spring:
  datasource:
    username: root
    password: 123456
    url: jdbc:mysql://127.0.0.1:3306/test?serverTimezone=UTC
    driver-class-name: com.mysql.cj.jdbc.Driver
    type: com.alibaba.druid.pool.DruidDataSource

    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，去掉后监控界面sql无法统计，'wall'用于防火墙
    filters: stat,wall,log4j
    maxPoolPreparedStatementPerConnectionSize: 20
    useGlobalDataSourceStat: true
    connectionProperties: druid.stat.mergeSql=true;druid.stat.slowSqlMillis=500

3、绑定配置&配置监控

import com.alibaba.druid.pool.DruidDataSource;
import com.alibaba.druid.support.http.StatViewServlet;
import com.alibaba.druid.support.http.WebStatFilter;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.boot.web.servlet.FilterRegistrationBean;
import org.springframework.boot.web.servlet.ServletRegistrationBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

import javax.sql.DataSource;
import java.util.Arrays;
import java.util.HashMap;
import java.util.Map;


@Configuration
public class DruidConfig {

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

    //配置Druid的监控
    //1、配置一个管理后台的Servlet
    @Bean
    public ServletRegistrationBean statViewServlet(){
        ServletRegistrationBean bean = new ServletRegistrationBean(new StatViewServlet(), "/druid/*");
        Map<String,String> initParams = new HashMap<>();

        initParams.put("loginUsername","admin");
        initParams.put("loginPassword","123456");
        initParams.put("allow","");//默认就是允许所有访问
        initParams.put("deny","192.168.15.21");

        bean.setInitParameters(initParams);
        return bean;
    }


    //2、配置一个web监控的filter
    @Bean
    public FilterRegistrationBean webStatFilter(){
        FilterRegistrationBean bean = new FilterRegistrationBean();
        bean.setFilter(new WebStatFilter());

        Map<String,String> initParams = new HashMap<>();
        initParams.put("exclusions","*.js,*.css,/druid/*");

        bean.setInitParameters(initParams);

        bean.setUrlPatterns(Arrays.asList("/*"));

        return  bean;
    }
}

4、运行：http://localhost:8080/druid/login.html，发现可以进入后台监控页面

创建表和bean

DROP TABLE IF EXISTS `employee`;
CREATE TABLE `employee` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `lastName` varchar(255) DEFAULT NULL,
  `email` varchar(255) DEFAULT NULL,
  `gender` int(2) DEFAULT NULL,
  `d_id` int(11) DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8;


DROP TABLE IF EXISTS `department`;
CREATE TABLE `department` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `departmentName` varchar(255) DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8;

public class Employee {
    private Integer id;
    private String lastName;
    private Integer gender;
    private String email;
    private Integer dId;
    
    ******
}

public class Department {
    private Integer id;
    private String departmentName;

	*******

注解方式使用mybatis

1、dao层：

import com.oceanstar.springboot_mybatis.domain.Department;
import org.apache.ibatis.annotations.*;

//指定这是一个操作数据库的mapper
@Mapper
public interface DepartmentMapper {

    @Select("select * from department where id=#{id}")
    public Department getDeptById(Integer id);

    @Delete("delete from department where id=#{id}")
    public int deleteDeptById(Integer id);

    @Options(useGeneratedKeys = true,keyProperty = "id")
    @Insert("insert into department(departmentName) values(#{departmentName})")
    public int insertDept(Department department);

    @Update("update department set departmentName=#{departmentName} where id=#{id}")
    public int updateDept(Department department);
}

测试：

import com.oceanstar.springboot_mybatis.domain.Department;
import com.oceanstar.springboot_mybatis.mapper.DepartmentMapper;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;

@SpringBootTest
class SpringbootMybatisApplicationTests {

    @Autowired
    DepartmentMapper departmentMapper;
    @Test
    void getDeptbyid() {
        System.out.println(departmentMapper.getDeptById(2));;
    }

    @Test
    void updateDept(){
        Department department = departmentMapper.getDeptById(2);
        department.setDepartmentName("bbbb");


        System.out.println(  departmentMapper.updateDept(department));
    }

    @Test
    void insertDept(){
        Department department = new Department();
        department.setDepartmentName("aaa");
        System.out.println(departmentMapper.insertDept(department));;
    }

    @Test
    void deleteDept(){
        System.out.println(departmentMapper.deleteDeptById(1));
    }

}

MapperScan

使用MapperScan批量扫描所有的Mapper接口；
@MapperScan(value = "com.atguigu.springboot.mapper")
@SpringBootApplication
public class SpringBoot06DataMybatisApplication {

	public static void main(String[] args) {
		SpringApplication.run(SpringBoot06DataMybatisApplication.class, args);
	}
}

自定义MyBatis的配置规则

给容器中添加一个ConfigurationCustomizer；

import org.mybatis.spring.boot.autoconfigure.ConfigurationCustomizer;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

@Configuration
public class MyBatisConfig {
    @Bean
    public ConfigurationCustomizer configurationCustomizer(){
        return  new ConfigurationCustomizer() {
            @Override  
            public void customize(org.apache.ibatis.session.Configuration configuration) {
                configuration.setMapUnderscoreToCamelCase(true); // 驼峰命名法
            }
        };
    }
}

来源：CSDN

作者：Ocean&&Star

链接：https://blog.csdn.net/zhizhengguan/article/details/104052122