时间：2020-12-02 12:23:57 | 栏目：JAVA代码 | 点击：次
序言：
此前，我们主要通过XML来书写SQL和填补对象映射关系。在SpringBoot中我们可以通过注解来快速编写SQL并实现数据访问。（仅需配置：mybatis.configuration.map-underscore-to-camel-case=true）。为了方便大家，本案例提供较完整的层次逻辑SpringBoot+MyBatis+Annotation。
具体步骤
1. 引入依赖
在pom.xml 引入ORM框架（Mybaits-Starter）和数据库驱动（MySQL-Conn）的依赖。
<?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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<!--继承信息 -->
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.0.0.M4</version>
<relativePath/>
</parent>
<!--依赖管理 -->
<dependencies>
<dependency> <!--添加Web依赖 -->
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency> <!--添加Mybatis依赖 -->
<groupId>org.mybatis.spring.boot</groupId>
<artifactId>mybatis-spring-boot-starter</artifactId>
<version>1.3.1</version>
</dependency>
<dependency><!--添加MySQL驱动依赖 -->
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<scope>runtime</scope>
</dependency>
<dependency><!--添加Test依赖 -->
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
</dependencies>
</project>
2. 添加数据源
在application.yml 添加数据源，以及开启Mybaits的驼峰映射功能。
spring: datasource: url: jdbc:mysql://localhost:3306/socks?useSSL=false username: root password: root driver-class-name: com.mysql.jdbc.Driver mybatis: configuration: map-underscore-to-camel-case: true #开启驼峰映射
3. 编写数据层代码
// POJO类如下：
public class User {
private String userId;
private String username;
private String password;
// Getters & Setters ..
}
// 数据层代码如下：
public interface UserMapper {
@Select("select * from t_user where 1=1")
List<User> list();
@Select("select * from t_user where username like #{username}")
List<User> findByUsername(String username);
@Select("select * from t_user where user_id like #{userId}")
User getOne(String userId);
@Delete("delete from t_user where user_id like #{userId}")
int delete(String userId);
}
4. 添加数据库记录
在Navicat 连接本地数据库，随便打开查询窗口，复制下面这段脚本，点击执行即可。
DROP DATABASE IF EXISTS `socks`;
CREATE DATABASE `socks`;
USE `SOCKS`;
DROP TABLE IF EXISTS `t_user`;
CREATE TABLE `t_user` (
`USER_ID` varchar(50) ,
`USERNAME` varchar(50) ,
`PASSWORD` varchar(50)
) ;
INSERT INTO `t_user` VALUES ('1', 'admin', 'admin');
INSERT INTO `t_user` VALUES ('2', 'yizhiwazi', '123456');
5. 启动项目
@SpringBootApplication
@MapperScan("com.hehe.mapper") //扫描Mapper接口
public class MybatisApplication {
public static void main(String[] args) {
SpringApplication.run(MybatisApplication.class, args);
}
}
6. 单元测试
import static org.assertj.core.api.Assertions.assertThat;
@RunWith(SpringRunner.class)
@SpringBootTest
public class MybatisApplicationTest {
@SuppressWarnings("all")
@Autowired
UserMapper userMapper;
@Test
public void test_db() {
//开始进行测试
assertThat(userMapper.list().size()).isGreaterThan(1);
assertThat(userMapper.getOne("1")).isNotEqualTo(null);
assertThat(userMapper.getOne("xxx")).isEqualTo(null);
}
}