[Java知识库]SpringBoot+MyBatis快速搭建项目

创建SpringBoot项目

引入相关依赖

		<!-- web核心依赖 -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <!-- mybatis -->
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>2.2.2</version>
        </dependency>
        <!-- 自动创建管理表依赖actable, 如果想手动管理可以不要这个依赖 -->
        <dependency>
            <groupId>com.gitee.sunchenbin.mybatis.actable</groupId>
            <artifactId>mybatis-enhance-actable</artifactId>
            <version>1.5.0.RELEASE</version>
        </dependency>
        
        <!-- 可以根据自己的需求配置数据库， 如果嫌麻烦直接使用H2数据库 -->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <scope>runtime</scope>
        </dependency>

        <dependency>
            <groupId>com.h2database</groupId>
            <artifactId>h2</artifactId>
            <version>2.1.212</version>
            <scope>runtime</scope>
        </dependency>

创建相应的目录结构

创建Entity

这里的@Table, @Id, @Column用actable或者java自己的都可以

@Data
@Builder
@Table(name = "tb_user")
public class User implements Serializable{

    /**
     * 
     */
    private static final long serialVersionUID = -8720709928795156685L;

    @Id
    private long id;
    
    @Column
    private String username;
    
    @Column
    private String password;
}

创建Mapper接口

@Mapper
public interface UserMapper {

    List<User> findAll();
    
    void save(User user);
}

Mapper文件映射

UserMapper.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.example.demo.mapper.UserMapper">
 
    <!-- findAll返回的是列表，需要手动映射 -->
    <resultMap type="com.example.demo.model.User" id="userMap">
        <id column="id" property="id" jdbcType="INTEGER" />
        <result column="username" property="username" jdbcType="VARCHAR" />
        <result column="password" property="password" jdbcType="VARCHAR" />
    </resultMap>
    
    <select id="findAll" resultType="com.example.demo.model.User" resultMap="userMap">
        SELECT * FROM tb_user
    </select>
    
    <insert id="save" parameterType="com.example.demo.model.User">
        insert into tb_user values(#{id}, #{username}, #{password})
    </insert>
</mapper>

创建接口

UserService.java

public interface UserService {

    List<User> findAll();
    
    void save(User user);
}

创建实现类

UserServiceImpl.java

@Service
public class UserServiceImpl implements UserService{
    
    @Autowired
    UserMapper userMapper;

    @Override
    public List<User> findAll() {
        // 为了方便先insert一条数据
        User user = User.builder()
                .id(111)
                .username("helloworld")
                .password("still helloworld")
                .build();
        save(user);
        return userMapper.findAll();
    }

    @Override
    public void save(User user) {
        userMapper.save(user);
    }

}

创建Controller

UserController.java

@RestController
@RequestMapping("/users")
public class UserController {

    @Autowired
    private UserService userService;
    
    @GetMapping
    public List<User> findAll(){
        return userService.findAll();
    }
}

主程序入口类配置

MybatisDemoApplication.java

/*
 * com.gitee.sunchenbin.mybatis.actable.dao.* 和 
 * com.gitee.sunchenbin.mybatis.actable.manager.* 是actable的官方配置，照抄就行
 */
@SpringBootApplication
@MapperScan({ "com.gitee.sunchenbin.mybatis.actable.dao.*", "com.example.demo.mapper"})
@ComponentScan(basePackages = { "com.gitee.sunchenbin.mybatis.actable.manager.*", "com.example.demo.*"})
public class MybatisDemoApplication {

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

}

配置文件

server:
  port: 8888

spring:
  datasource:
# --- begin mysql config --- 
#    url: jdbc:mysql://localhost:3306/mybatis_demo?characterEncoding=UTF-8
#    driver-class-name: com.mysql.cj.jdbc.Driver
#    username: your_database_username
#    password: your_database_password
# --- end mysql config --- 
    url: jdbc:h2:mem:testdb;mode=MySQL
    driver-class-name: org.h2.Driver
    
mybatis: 
  mapper-locations:
  - classpath:mapper/*.xml # 自己的mapper配置目录
  # actable的官方配置，照抄就ok
  - classpath*:com/gitee/sunchenbin/mybatis/actable/mapping/*/*.xml
  table:
    # create: 会删除原有所有数据在新建; none:不作任何处理; update: 不存在新建，存在更新
    auto: update 
  model:
    pack: com.example.demo.model # entity目录
  database:
    type: mysql

启动并测试

如果之前的配置用的是H2数据库的话，直接启动后访问http://localhost:8888/users会返回如下数据，如果用的是mysql数据库的配置，请确定指定的数据库已安装并且已启动。

github源码

感谢阅读