1.引入依赖

		<dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>2.1.1</version>
        </dependency>
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid</artifactId>
            <version>1.1.8</version>
        </dependency>

2.编写application.yml配置文件

spring:
  datasource:
    username: root
    password: 123456
    url: jdbc:mysql://localhost:3306/bike?serverTimezone=UTC
    driver-class-name: com.mysql.jdbc.Driver
    type: com.alibaba.druid.pool.DruidDataSource
    initialSize: 5
    minIdle: 5
    maxActive: 20
    maxWait: 60000
    timeBetweenEvictionRunsMillis: 60000
    minEvictableIdleTimeMillis: 30000
    validationQuery: SELECT 1 FROM DUAL
    testWhileIdle: true
    testOnBorrow: false
    testOnReturn: false
    poolPreparedStatements: true

    filters: stat,wall,log4j
    maxPoolPreparedStatementPerConnectionSize: 20
    useGlobalDataSourceStat: true
    connectionProperties: druid.stat.mergeSql=true;druid.stat.slowSqlMills=500

#配置文件的mybatis的配置设置，注解方式可以不用
mybatis:
  #config-location: classpath:mybatis/mybatis-config.xml 可以没有这个
  mapper-locations: classpath:mybatis/mapper/*.xml

3.编写配置类MybatisConfig.java

/**
 * 自定义mybatis的属性封装名称 驼峰命名
 */
@Configuration
public class MyBatisConfig {

    public ConfigurationCustomizer configurationCustomizer(){
        return new ConfigurationCustomizer() {
            @Override
            public void customize(org.apache.ibatis.session.Configuration configuration) {
                configuration.setMapUnderscoreToCamelCase(true);
            }
        };
    }
}

4.编写DruidConfig.java

@Configuration
public class DruidConfig {

    //绑定属性自己配置文件中创建的Druid连接池属性
    @ConfigurationProperties(prefix = "spring.datasource")
    @Bean
    public DataSource druid(){
        return new DruidDataSource();
    }

    //配置Druid监控
    //1.配置一个管理后台的servlet
    @Bean
    public ServletRegistrationBean statViewServlet(){
        ServletRegistrationBean bean = new ServletRegistrationBean(new StatViewServlet(),"/driud/*");
        Map<String,String> initParams = new HashMap<>();
        initParams.put("loginUsername","admin");
        initParams.put("loginPassword","123456");
        initParams.put("allow","");//默认允许所有
        bean.setInitParameters(initParams);
        return bean;

    }
    //2.配置一个监控的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;
    }
}

6.Employee实体类

public class Employee {

    private Integer id;
    private String lastName;
    private Integer gender;
    private String email;
    private Integer dId;

	//省略getter setter  等等
}

7.编写mapper的xml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.wang.springboot.mapper.EmployeeMapper">
   <!-- -->
    <select id="getEmpById" resultType="com.wang.springboot.bean.Employee">
        select * from employee where id = #{id}
    </select>
    
    <insert id="insertEmp">
        insert into employee(lastName,email,gender,d_id) values(#{lastName},#{email},#{gender},#{dId})
    </insert>
</mapper>