一、配置文件方式实现
前提:已将数据库驱动包引入,并且已配置好数据源信息
1、引入依赖

<!-- mybatis依赖包 -->
    <dependency>
		<groupId>org.mybatis.spring.boot</groupId>
		<artifactId>mybatis-spring-boot-starter</artifactId>
		<version>1.3.2</version>
    </dependency>

2、添加配置信息

#mybatis配置信息
#mybatis.config-location=classpath:mybatis/mybatis-config.xml
#mapper映射文件位置
mybatis.mapper-locations=classpath:mapper/*.xml
#配置xml文件中resultType返回值的包位置
mybatis.typeAliasesPackage=qingxia.tang.jpa.bean

3、写mapper接口类

package qingxia.tang.jpa.mapper;

import java.util.List;

import org.apache.ibatis.annotations.Result;
import org.apache.ibatis.annotations.Results;
import org.apache.ibatis.annotations.Select;

import qingxia.tang.jpa.bean.Cat;
/**
 * 需要使用@Mapper注解,不然SpringBoot无法扫描,或者在启动类中添加对mapper包扫描@MapperScan
 * @author tangqingxia
 *
 */

public interface CatMapper {
	/**
	 * xml配置文件方式
	 * @return
	 */
	public List<Cat> queryAllCats();

}

4、编写在resources文件中创建 mapper/CatMapper.xml映射文件
注意:
1.namespace中需要与使用@Mapper的接口对应
2.CatMapper.xml文件名称必须与使用@Mapper的接口一致
3.标签中的id必须与@Mapper的接口中的方法名一致,且参数一致

<?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" >
<!--
         注意:
	1.namespace中需要与使用@Mapper的接口对应
	2.CatMapper.xml文件名称必须与使用@Mapper的接口一致
	3.标签中的id必须与@Mapper的接口中的方法名一致,且参数一致
  -->
<mapper namespace= "qingxia.tang.jpa.mapper.CatMapper" >
    <resultMap id ="CatInfoMap" type="qingxia.tang.jpa.bean.Cat">
        <result column="id" property="id"/>
        <result column="name" property="name"/>
        <result column="age" property="age"/>
        <result column="address_id" property="addressId"/>
    </resultMap>

    <select id = "queryAllCats" resultMap="CatInfoMap">
        select id,name,age,address_id from cat
    </select>
</mapper>

5、编写service

package qingxia.tang.jpa.service;

import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import qingxia.tang.jpa.bean.Cat;
import qingxia.tang.jpa.mapper.CatMapper;

@Service
public class CatMapperService {
	
	@Autowired
	private CatMapper catMapper;
	
	public List<Cat> queryAllCats(){
		List<Cat> queryAllCats = catMapper.queryAllCats();
		return queryAllCats;
	}

}

6、编写controller

package qingxia.tang.jpa.controller;

import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;

import qingxia.tang.jpa.bean.Cat;
import qingxia.tang.jpa.service.CatMapperService;

@Controller
public class CatMapperController {
	
	@Autowired
	private CatMapperService catMapperService;
	
	@ResponseBody
	@RequestMapping(value="/queryAllCats",produces={"application/json"})
	public List<Cat> queryAllCats(){
		List<Cat> queryAllCats = catMapperService.queryAllCats();
		return queryAllCats;
	}
	

}

7、在启动类app.java添加@MapperScan(“qingxia.tang.jpa.mapper”)注解,也可以在mapper接口类
添加@Mapper注解代替,但此注解需要在每个mapper接口类添加

package qingxia.tang;

import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
/**
 * SpringBootApplication注解相当于Controller注解和responseBody注解
 * 在使用mybatis时,需要在启动类app.java添加@MapperScan("qingxia.tang.jpa.mapper")注解,
 * 也可以在mapper接口类添加@Mapper注解代替,但此注解需要在每个mapper接口类添加
 * 
 * @author tangqingxia
 *
 */
@MapperScan("qingxia.tang.jpa.mapper")
@SpringBootApplication
public class App /** extends WebMvcConfigurerAdapter */{
	
	/**
	 * 配置FastJson方式一
	 * 1、继承extends WebMvcConfigurerAdapter类
	 * 2、重写configureMessageConverters方法
	 */
	/**
	@Override
	public void configureMessageConverters(List<HttpMessageConverter<?>> converters) {
		super.configureMessageConverters(converters);
		//定义convert的转换对象
		FastJsonHttpMessageConverter fastConverter = new FastJsonHttpMessageConverter();
		//添加fastjson的配置信息
		FastJsonConfig fastJsonConfig = new FastJsonConfig();
		fastJsonConfig.setSerializerFeatures(SerializerFeature.PrettyFormat);
		//把配置信息添加到对象中
		fastConverter.setFastJsonConfig(fastJsonConfig);
		//把新建的对象替换返回
		converters.add(fastConverter);
	}
	*/
	
	/**
     * 配置FastJson方式二
     * Bean注入的方式
     * @return  HttpMessageConverters
     */
	/**
    @Bean
    public HttpMessageConverters fastJsonHttpMessageConverters() {
        // 1.定义一个converters转换消息的对象
        FastJsonHttpMessageConverter fastConverter = new FastJsonHttpMessageConverter();
        // 2.添加fastjson的配置信息,比如: 是否需要格式化返回的json数据
        FastJsonConfig fastJsonConfig = new FastJsonConfig();
        fastJsonConfig.setSerializerFeatures(SerializerFeature.PrettyFormat);
        // 3.在converter中添加配置信息
        fastConverter.setFastJsonConfig(fastJsonConfig);
        // 4.将converter赋值给HttpMessageConverter
        HttpMessageConverter<?> converter = fastConverter;
        // 5.返回HttpMessageConverters对象
        return new HttpMessageConverters(converter);
    }
    */
	
	public static void main(String[] args) {
		SpringApplication.run(App.class, args);
	}

}

8、测试

spring boot mysql yml 配置_spring

二、注解方式实现
1、引入依赖

<!-- mybatis依赖包 -->
    <dependency>
		<groupId>org.mybatis.spring.boot</groupId>
		<artifactId>mybatis-spring-boot-starter</artifactId>
		<version>1.3.2</version>
    </dependency>

2、写mapper接口类

package qingxia.tang.jpa.mapper;

import java.util.List;

import org.apache.ibatis.annotations.Result;
import org.apache.ibatis.annotations.Results;
import org.apache.ibatis.annotations.Select;

import qingxia.tang.jpa.bean.Cat;
/**
 * 需要使用@Mapper注解,不然SpringBoot无法扫描,或者在启动类中添加对mapper包扫描@MapperScan
 * @author tangqingxia
 *
 */

public interface CatMapper {
	
	/**
	 * 注解方式
	 * 如属性名和列名不一致的需加上@Result注解进行结果返回
	 * @return
	 */
	@Select("select t.id,t.name,t.age,t.address_id from cat t")
	@Results({
        @Result(property = "addressId",  column = "address_id"),
    })
	public List<Cat> queryAllCatsByAnn();

}

3、编写service

package qingxia.tang.jpa.service;

import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import qingxia.tang.jpa.bean.Cat;
import qingxia.tang.jpa.mapper.CatMapper;

@Service
public class CatMapperService {
	
	@Autowired
	private CatMapper catMapper;
	
	public List<Cat> queryAllCatsByAnn(){
		List<Cat> queryAllCatsByAnn = catMapper.queryAllCatsByAnn();
		return queryAllCatsByAnn;
	}

}

4、编写controller

package qingxia.tang.jpa.controller;

import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;

import qingxia.tang.jpa.bean.Cat;
import qingxia.tang.jpa.service.CatMapperService;

@Controller
public class CatMapperController {
	
	@Autowired
	private CatMapperService catMapperService;
	
	@ResponseBody
	@RequestMapping(value="queryAllCatsByAnn",produces={"application/json"})
	public List<Cat> queryAllCatsByAnn(){
		List<Cat> queryAllCatsByAnn = catMapperService.queryAllCatsByAnn();
		return queryAllCatsByAnn;
	}
	

}

5、在启动类app.java添加@MapperScan(“qingxia.tang.jpa.mapper”)注解,也可以在mapper接口类
添加@Mapper注解代替,但此注解需要在每个mapper接口类添加

package qingxia.tang;

import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
/**
 * SpringBootApplication注解相当于Controller注解和responseBody注解
 * 在使用mybatis时,需要在启动类app.java添加@MapperScan("qingxia.tang.jpa.mapper")注解,
 * 也可以在mapper接口类添加@Mapper注解代替,但此注解需要在每个mapper接口类添加
 * 
 * @author tangqingxia
 *
 */
@MapperScan("qingxia.tang.jpa.mapper")
@SpringBootApplication
public class App /** extends WebMvcConfigurerAdapter */{
	
	/**
	 * 配置FastJson方式一
	 * 1、继承extends WebMvcConfigurerAdapter类
	 * 2、重写configureMessageConverters方法
	 */
	/**
	@Override
	public void configureMessageConverters(List<HttpMessageConverter<?>> converters) {
		super.configureMessageConverters(converters);
		//定义convert的转换对象
		FastJsonHttpMessageConverter fastConverter = new FastJsonHttpMessageConverter();
		//添加fastjson的配置信息
		FastJsonConfig fastJsonConfig = new FastJsonConfig();
		fastJsonConfig.setSerializerFeatures(SerializerFeature.PrettyFormat);
		//把配置信息添加到对象中
		fastConverter.setFastJsonConfig(fastJsonConfig);
		//把新建的对象替换返回
		converters.add(fastConverter);
	}
	*/
	
	/**
     * 配置FastJson方式二
     * Bean注入的方式
     * @return  HttpMessageConverters
     */
	/**
    @Bean
    public HttpMessageConverters fastJsonHttpMessageConverters() {
        // 1.定义一个converters转换消息的对象
        FastJsonHttpMessageConverter fastConverter = new FastJsonHttpMessageConverter();
        // 2.添加fastjson的配置信息,比如: 是否需要格式化返回的json数据
        FastJsonConfig fastJsonConfig = new FastJsonConfig();
        fastJsonConfig.setSerializerFeatures(SerializerFeature.PrettyFormat);
        // 3.在converter中添加配置信息
        fastConverter.setFastJsonConfig(fastJsonConfig);
        // 4.将converter赋值给HttpMessageConverter
        HttpMessageConverter<?> converter = fastConverter;
        // 5.返回HttpMessageConverters对象
        return new HttpMessageConverters(converter);
    }
    */
	
	public static void main(String[] args) {
		SpringApplication.run(App.class, args);
	}

}

6、测试

spring boot mysql yml 配置_List_02