526互联

Springboot自定义starter

发布时间 2023-11-20 22:10:00作者: 今晚三分饱

Springboot自定义sarter

这里通过自定义mybatis的starter来简单进行分析理解

步骤：

  • 创建dmybatis-spring-boot-autoconfigure模块，提供自动配置功能，并定义配置文件META-INF/spring/xxx.imports

  • 创建dmybatis-spring-boot-starter模块，在starter中引入自动配置模块

    创建项目：

1.autoconfigure模块

在dmybatis-spring-boot-autoconfigure模块的pom.xml中引入对应的依赖坐标

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter</artifactId>
            <version>3.1.4</version>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-jdbc</artifactId>
            <version>3.1.5</version>
        </dependency>

        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.5.13</version>
        </dependency>

        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis-spring</artifactId>
            <version>3.0.2</version>
        </dependency>

在当前模块中创建config包，包内创建配置类MyBatisAutoConfig,包结构如下：

在类上方添加注解，同时注入SqlSessionFactoryBean和MapperScannerConfigure对象

具体代码如下：

@AutoConfiguration
public class MyBatisAutoConfig {

    //SqlSessionFactoryBean
    @Bean
    public SqlSessionFactoryBean sqlSessionFactoryBean(DataSource dataSource){
        SqlSessionFactoryBean sqlSessionFactoryBean = new SqlSessionFactoryBean();
        sqlSessionFactoryBean.setDataSource(dataSource);
        return sqlSessionFactoryBean;
    }

    //MapperScannerConfigure
    @Bean
    public MapperScannerConfigurer mapperScannerConfigurer(BeanFactory beanFactory){
        MapperScannerConfigurer mapperScannerConfigurer = new MapperScannerConfigurer();
        //扫描的包:启动类所在的包及其子包
        List<String> packages = AutoConfigurationPackages.get(beanFactory);
        String p = packages.get(0);
        mapperScannerConfigurer.setBasePackage(p);

        //扫描的注解
        mapperScannerConfigurer.setAnnotationClass(Mapper.class);
        return mapperScannerConfigurer;
    }


}

新建resources包，在包下新建.imports配置文件

配置文件中配置：

com.qym.config.MyBatisAutoConfig
2.starter模块：

在sterter模块的pom.xml文件中引入依赖：

<dependency>
      <groupId>com.qym</groupId>
      <artifactId>dmybatis-spring-boot-autoconfigure</artifactId>
      <version>1.0-SNAPSHOT</version>
    </dependency>

同时为了在引入starter以来后，对相应的依赖进行排除等操作，为了更方便操作，所以将starter中的相应依赖引入(官方推荐做法)

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter</artifactId>
            <version>3.1.4</version>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-jdbc</artifactId>
            <version>3.1.5</version>
        </dependency>

        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.5.13</version>
        </dependency>

        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis-spring</artifactId>
            <version>3.0.2</version>
        </dependency>

将starter中的无关文件删除

3.测试自定义starter类：

新建测试模块并在pom.xml中引入自定义syarter依赖

        <dependency>
            <groupId>com.qym</groupId>
            <artifactId>dmybatis-spring-boot-starter</artifactId>
            <version>1.0-SNAPSHOT</version>
        </dependency>

编写简单的用户查找方法：

UserController.class

@RestController
public class UserController {

    @Autowired
    private UserService userService;

    @RequestMapping("/getById")
    public User getById(Integer id) {
        return userService.getById(id);
    }

}

UserService接口

public interface UserService {

    public User getById(Integer id);
}

UserServiceImpl实现类

@Service
public class UserServiceImpl implements UserService {

    @Autowired
    private UserMapper userMapper;

    @Override
    public User getById(Integer id) {
        return userMapper.getById(id);
    }
}

UserMapper接口

@Mapper
public interface UserMapper {

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

}

user实体类

@Data
@NoArgsConstructor
@AllArgsConstructor
public class User {

    private Integer id;
    private String username;
    private String password;
    private String phone;
    private String info;
    private Integer status;
    private Integer balance;
    private LocalDateTime createTime;
    private LocalDateTime updateTime;

}

启动类Springboot3QuickstartApplication

@SpringBootApplication
public class Springboot3QuickstartApplication {

    public static void main(String[] args) {
        SpringApplication.run(Springboot3QuickstartApplication.class, args);
    }

}

运行结果：

由于没有开启驼峰命名，所以创建时间和更新时间查询出来时null。

通过测试案例可以发现所配置的mybatis的starter启动没有问题