（2）. 添加 application.yml（yml比起 properties文件看起来清爽很多，简介很多）
spring: datasource: name: spring_boot_mybatis url: jdbc:mysql://localhost:3306/mybatis_demo1 username: root password: 1486145487 # type: com.alibaba.druid.pool.DruidDataSource # 使用druid 数据源 driver-class-name: com.mysql.jdbc.Driver # dbcp2: # min-idle: 1 # max-idle: 2 # initial-size: 1 # time-between-eviction-runs-millis: 3000 # min-evictable-idle-time-millis: 300000 # validation-query: SELECT "ZTM" FROM DUAL # test-while-idle: true # test-on-borrow: false # test-on-return: false mybatis: mapper-locations: classpath:mapper/UserMapper.xml,classpath:mapper/StudentMapper.xml type-aliases-package: xatu.zsl.entity注意：注释地方是配置数据库连接池的东西（不配置也可以，，测试感觉不出来） （3）. 配置Mybatis 的mapper文件，，这个文件是mybatis映射的核心文件是必须的。 在这里扩展一下，放两个mapper文件，内容一样只是为了说明，springBoot整合Mybatis如何配置多个mapper文件
StudentMapper.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="xatu.zsl.mapper.StudentMapper" > <insert id="save" parameterType="xatu.zsl.entity.User"> insert into t_user(username,age) values(#{userName,jdbcType=VARCHAR},#{age,jdbcType=NUMERIC}) </insert> <select id="selectById" resultType="xatu.zsl.entity.User"> select * from t_user where id = #{id,jdbcType=NUMERIC} </select> <update id="updateById" parameterType="xatu.zsl.entity.User"> update t_user set username = #{userName,jdbcType=VARCHAR} , age = #{age,jdbcType=NUMERIC} where id = #{id,jdbcType=NUMERIC} </update> <delete id="deleteById"> delete from t_user where id = #{id,jdbcType=NUMERIC} </delete> <select id="queryAll" resultType="xatu.zsl.entity.User"> select * from t_user </select> </mapper>（4）. 设置接口 StudentMapper
package xatu.zsl.mapper; import org.apache.ibatis.annotations.Mapper; import org.springframework.stereotype.Component; import xatu.zsl.entity.User; import java.util.List; /** * Created by zsl on 2017/8/6. */ @Component @Mapper public interface StudentMapper { int save(User user); User selectById(Integer id); int updateById(User user); int deleteById(Integer id); List<User> queryAll(); }（5）. 编写实体类 User（为了方便就使用两个一样的mapper，能说明问题咋简单砸来）
package xatu.zsl.entity; import java.io.Serializable; /** * Created by zsl on 2017/8/6. */ public class User implements Serializable { private static final long serialVersionUID = 8809101560720973267L; private Integer id; private String userName; private Integer age; public Integer getId() { return id; } public void setId(Integer id) { this.id = id; } public String getUserName() { return userName; } public void setUserName(String userName) { this.userName = userName; } public Integer getAge() { return age; } public void setAge(Integer age) { this.age = age; } @Override public String toString() { return "User [id=" + id + ", userName=" + userName + ", age=" + age + "]"; } }（6）. 启动文件不用变，，使用test 文件测试
package xatu.zsl; import org.junit.Test; import org.junit.runner.RunWith; import org.springframework.boot.test.context.SpringBootTest; import org.springframework.test.context.junit4.SpringRunner; //@RunWith(SpringRunner.class) //@SpringBootTest //public class SpringBootMybatisApplicationTests { // // @Test // public void contextLoads() { // } // //} import org.springframework.beans.factory.annotation.Autowired; import xatu.zsl.entity.User; import xatu.zsl.mapper.StudentMapper; import xatu.zsl.mapper.UserMapper; import xatu.zsl.service.UserService; @RunWith(SpringRunner.class) @SpringBootTest() //相当于 --spring.profiles.active=dev //@ActiveProfiles(value="dev") public class SpringBootMybatisApplicationTests { @Autowired private UserMapper mapper; @Autowired private StudentMapper studentMapper; @Test public void testInsert() { User user = new User(); user.setUserName("张飞"); user.setAge(50); mapper.save(user); System.out.println("插入用户信息" + user.getUserName()); } @Test public void testSelect() { User user = mapper.selectById(1); System.out.println("查找用户成功：" + user); } @Test public void testUpdate() { User user = mapper.selectById(1); System.out.println("修改用户信息初：" + user); user.setAge(24); mapper.updateById(user); user = mapper.selectById(1); System.out.println("修改用户信息末：" + user); } @Autowired private UserService userService; @Test public void testTransactional() { System.out.println("测试事务处理"); //测试事务处理 try { userService.insetUser(); } catch (Exception e) { e.printStackTrace(); System.out.println("事务处理异常"); } } @Test public void testSelectStudent() { User user = studentMapper.selectById(1); System.out.println("studentMapper查找用户成功：" + user); } }测试运行截图：
（2）. springBoot整合Mybatis如何配置多个mapper文件，需要在applaction.yml中配置：
mybatis: mapper-locations: classpath:mapper/UserMapper.xml,classpath:mapper/StudentMapper.xml（3）. @Mapper 注解是springBoot整合Mybatis独有的，，mybatis木有。
import org.apache.ibatis.annotations.Mapper; 鼠小 认证博客专家 一个萌汉子 未来的路是黑的，我不知道怎么走，我需要做的就是先走着。https://smallzheng.blog.csdn.net/