「Spring Boot 系列」08. Spring Boot整合MyBatis

Spring Boot整合MyBatis步骤：

1. 新建Spring Boot工程，并选择需要使用的技术集

pom.xml文件

 <dependency>
    <groupId>org.mybatis.spring.bootgroupId>
    <artifactId>mybatis-spring-boot-starterartifactId>
    <version>2.2.2version>
dependency>

<dependency>
    <groupId>mysqlgroupId>
    <artifactId>mysql-connector-javaartifactId>
    <scope>runtimescope>
dependency>

<dependency>
    <groupId>org.springframework.bootgroupId>
    <artifactId>spring-boot-starter-testartifactId>
    <scope>testscope>
dependency>

2. 设置相关参数（数据源）

application.yml

#配置相关信息
spring:
  datasource:
    driver-class-name: com.mysql.cj.jdbc.Driver  #com.mysql.jdbc.Driver该驱动类过时
    url: jdbc:mysql://localhost:3306/test?serverTimezone=UTC
    username: root
    password: root

3. 编写一个实体类 Person.java

public class Person {

    private Integer id;
    private String name;
    private String city;

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getCity() {
        return city;
    }

    public void setCity(String city) {
        this.city = city;
    }

    @Override
    public String toString() {
        return "Person{" +
                "id=" + id +
                ", name='" + name + '\'' +
                ", city='" + city + '\'' +
                '}';
    }
}

4. 定义数据层接口与映射配置（两种方式，任意一种都可）

• 方式一：纯注解开发

@Mapper  //SQL映射添加@Mapper注解方便被容器识别
public interface PersonDao {

    @Select("select * from person where id = #{id}")
    public Person getById(Integer id);
}

• 方式二：xml开发

1. 新建一个PersonMapper接口

@Mapper
public interface PersonMapper {

    public List<Person> findAll();
}

2. resources下新建一个mapper文件夹并在里面新建 PersonMapper.xml文件

DOCTYPE mapper
        PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.ityun.springbootstudy.mapper.PersonMapper">

    <select id="findAll" resultType="person">
        select * from person
    select>

mapper>

3. 在application.yml 中添加MyBatis配置

#MyBatis配置
mybatis:
  mapper-locations: classpath:mapper/*Mapper.xml  #mapper映射文件路径
  type-aliases-package: com.ityun.springbootstudy.domain #定义实体类的别名

5. 测试类中注入dao接口，测试功能

@SpringBootTest
class SpringbootStudyApplicationTests {

    @Autowired
    private PersonDao personDao;

    @Autowired
    private PersonMapper personMapper;

    @Test
    public void findTest() {
        System.out.println(personDao.getById(1));
    }

    @Test
    public void findAllTest(){
        List<Person> list = personMapper.findAll();
        System.out.println(list);
    }

}

6. 运行结果