Spring Boot MyBatis

依赖声明：

# pom.xml

<parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>1.5.14.RELEASE</version>
</parent>
<dependencies>
    <dependency>
        <groupId>org.mybatis.spring.boot</groupId>
        <artifactId>mybatis-spring-boot-starter</artifactId>
        <version>1.3.2</version>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-test</artifactId>
        <scope>test</scope>
    </dependency>
    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <version>5.1.40</version>
    </dependency>
</dependencies>

mybatis-spring-boot-starter：MyBatis 启动器。

数据库表：

CREATE TABLE `employee` (
  `id` int(11) NOT NULL AUTO_INCREMENT COMMENT 'ID',
  `name` varchar(16) NOT NULL COMMENT '姓名',
  `age` int(11) NOT NULL COMMENT '性别',
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=2 DEFAULT CHARSET=utf8;

MySQL 数据库脚本

实体类：

package org.fanlychie.entity;
 
public class Employee {
	
    private Long id;
    
    private String name;
    
    private Integer age;
    
    // ignore getters and setters ...
    
    @Override
    public String toString() {
        return "Employee{" +
                "id=" + id +
                ", name='" + name + '\'' +
                ", age=" + age +
                '}';
    }
    
}

Mapper 配置文件：

# src/main/resources/mapper/EmployeeMapper.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="org.fanlychie.mapper.EmployeeMapper">
    
    <insert id="save" useGeneratedKeys="true" keyProperty="id" parameterType="Employee">
        INSERT INTO EMPLOYEE (
            ID, NAME, AGE
        ) VALUES (
            #{id}, #{name}, #{age}
        )
    </insert>
    
    <select id="selectAll" resultMap="EmployeeResultMap">
        SELECT * FROM EMPLOYEE
    </select>
    
    <resultMap id="EmployeeResultMap" type="Employee">
        <id property="id" column="ID" />
        <result property="name" column="NAME" />
        <result property="age" column="AGE" />
    </resultMap>
    
</mapper>

Mapper 接口：

package org.fanlychie.mapper;
 
public interface EmployeeMapper {
	
    Long save(Employee employee);
	
    List<Employee> selectAll();
	
}

只需声明接口，不需要编写额外的实现类。

Spring Boot 配置文件：

# src/main/resources/application.yml

spring:
  datasource:
    url: jdbc:mysql://127.0.0.1/test
    username: root
    password: root
    driver-class-name: com.mysql.jdbc.Driver
    tomcat:
      default-auto-commit: true
 
mybatis:
  mapper-locations: classpath:mapper/*.xml
  type-aliases-package: org.fanlychie.entity
 
logging:
  level:
    root: WARN
    org.fanlychie.mapper: DEBUG

mapper-locations：用来指定 MyBatis 的 Mapper 配置文件的位置。

type-aliases-package：指定类型别名的包。多个用逗号（,）或分号（;）分隔。 指定的包下所有的类型在 Mapper 配置文件中可以使用类的简单类名（如：org.fanlychie.entity.Employee 可以简写为 Employee）。

启动类：

@SpringBootApplication
@MapperScan("org.fanlychie.mapper")
public class Application {
	
    public static void main(String[] args) {
        SpringApplication.run(Application.class, args);
    }
	
}

MyBatis 启动器默认会搜索所有 @Mapper 的注解。这意味着你所有的 Mapper 接口都需要标注 @Mapper 注解。显然这样不够方便。@MapperScan 注解可以用来指定要扫描的 Mapper 接口的包路径。

单元测试：

@RunWith(SpringRunner.class)
@SpringBootTest
public class ApplicationTest {
	
    @Autowired
    private EmployeeMapper employeeMapper;
    
    @Test
    public void testSave() {
        Employee employee = new Employee();
        employee.setName("fanlychie");
        employee.setAge(23);
        employeeMapper.save(employee);
    }
    
    @Test
    public void testSelectAll() {
        List<Employee> employees = employeeMapper.selectAll();
        employees.forEach(System.out::println);
    }
    
}

示例项目开发环境：Java-8、Maven-3、IntelliJ IDEA-2018、Spring Boot-1.5.14.RELEASE
完整示例项目链接：spring-boot-mybatis-sample
参考文档文献链接：mybatis-spring-boot-autoconfigure