@Component

1. 定义：注解类、接口、注解、枚举。

 

@Target(ElementType.TYPE) /** Class, interface (including annotation type), or enum declaration */
@Retention(RetentionPolicy.RUNTIME)

 

 

2. spring 文档说明：

The @Repository annotation is a marker for any class that fulfills the role or stereotype (also known as Data Access Object or DAO) of a repository.

@Component is a generic stereotype for any Spring-managed component. @Repository, @Service, and @Controller are specializations of @Component for more specific use cases.

 

3. Automatically detecting classes and registering bean definitions 自动检测类和注册bean定义

3.1 @Configuration和@ComponentScan 联合使用，标明要扫描的包及其子包。

@Configuration
@ComponentScan(basePackages = "org.example")
public class AppConfig  {
    ...
}

可以简化为 @ComponentScan("org.example")。

也可以写多个包，用（,|;| ）分隔，如@ComponentScan("org.example,com,example")

3.2 使用filter 定制扫描

@Configuration
@ComponentScan(basePackages = "org.example",
        includeFilters = @Filter(type = FilterType.REGEX, pattern = ".*Stub.*Repository"),
        excludeFilters = @Filter(Repository.class))
public class AppConfig {
    ...
}