SpringBoot整合MyBatis

创建工程

创建SpringBoot工程

工程命名

可以暂不选择依赖

确认创建工程

指定maven仓库

pom

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.2.4.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.hkj</groupId>
    <artifactId>spring-boot-mybatis-demo</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>spring-boot-mybatis-demo</name>
    <description>Demo project for Spring Boot</description>

    <properties>
        <java.version>1.8</java.version>
    </properties>

    <dependencies>
        <!-- spring boot 相关依赖-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter</artifactId>
        </dependency>
        <!-- web 相关依赖 -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <!-- mysql驱动 -->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
        </dependency>
        <!-- spring boot和mybatis整合依赖 -->
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>1.3.0</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
            <exclusions>
                <exclusion>
                    <groupId>org.junit.vintage</groupId>
                    <artifactId>junit-vintage-engine</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>
</project>

yml

server:
  port: 8080

spring:
  datasource:
    name: test
    url: jdbc:mysql://127.0.0.1:3306/test?useUnicode=true&characterEncoding=UTF-8&serverTimezone=Asia/Shanghai
    username: root
    password: lovehkj
    driver-class-name: com.mysql.cj.jdbc.Driver

mybatis:
  mapper-locations: classpath:mapper/*.xml
  type-aliases-package: com.hkj.springbootmybatisdemo.entity.Person

项目包结构

包结构

Entity

//@Repository
public class Person {
    private String id;
    private String name;
    private int age;
    private String sex;

    public String getId() {
        return id;
    }

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

    public String getName() {
        return name;
    }

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

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }

    public String getSex() {
        return sex;
    }

    public void setSex(String sex) {
        this.sex = sex;
    }

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

Controller

@RestController
public class ControllerTest {
    @Autowired
    private ServiceTest serviceTest;

    @GetMapping(value = "/test/{id}")
    public String test(@PathVariable(value = "id") String id){
        String result = serviceTest.test(id);
        return result;
    }
}

Service Interface

public interface ServiceTest {
    String test(String id);
}

Service Impl

@Service
public class ServiceTestImpl implements ServiceTest {
    @Autowired
    private TestDao daoTest;

    public String test(String id){
        Person person = daoTest.test(id);
        String result = person.toString();
        return result;
    }
}

Dao Interface

@Mapper
public interface TestDao {
    Person test(String id);
}

Dao 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="com.hkj.springbootmybatisdemo.dao.TestDao">
    <select id="test" parameterType="string" resultType="com.hkj.springbootmybatisdemo.entity.Person">
        select * from person where id= #{id}
    </select>
</mapper>

启动类

@SpringBootApplication
public class SpringBootMybatisDemoApplication {

    public static void main(String[] args) {
        SpringApplication.run(SpringBootMybatisDemoApplication.class, args);
    }

}

浏览器中访问http://localhost:8080/test/0a3c0ed0b4354d27bbebb1ab1b53bb68进行测试
结果如下：

测试数据

与数据库中person表结果一致

person表

实际开发中，Dao Interface的数量会很多，如果在每个Dao Interface上都添加@Mapper注解会很麻烦，如果忘记添加，还会导致出错，可以通过在启动类上添加@MapperScan注解来配置Dao Interface扫描：

@SpringBootApplication
@MapperScan("com.hkj.springbootmybatisdemo.dao")// Dao Interface存放路径
public class SpringBootMybatisDemoApplication {

    public static void main(String[] args) {
        SpringApplication.run(SpringBootMybatisDemoApplication.class, args);
    }

}

添加此配置后，即可无需每个Dao Interface上都配置@Mapper注解，减少重复工作。

如要开启sql日志，配置yml

server:
  port: 8080

spring:
  datasource:
    name: test
    url: jdbc:mysql://127.0.0.1:3306/test?useUnicode=true&characterEncoding=UTF-8&serverTimezone=Asia/Shanghai
    username: root
    password: ljy19950703
    driver-class-name: com.mysql.cj.jdbc.Driver

mybatis:
  mapper-locations: classpath:mapper/*.xml
  type-aliases-package: com.hkj.springbootmybatisdemo.entity.Person
  configuration:
    log-impl: org.apache.ibatis.logging.stdout.StdOutImpl

重新访问测试接口，console打印日志如下：

console打印sql日志