Import注解

@Import(Cat.class)//可以把一个类当做一个Bean注入到Spring中

@Import(CatConfiguration.class)//可以把一个配置类注入到spring中

public class Cat {

    public void  miaomiao(){
        System.out.println("miaomiao");
    }
}

@Configuration
public class CatConfiguration {


    @Bean
    public Cat cat() {
        return new Cat();
    }
}

@Import(DogSelector.class)//可以DogSelector中返回的全类名数组都加入到spring中管理

public class DogSelector implements ImportSelector {
    @Override
    public String[] selectImports(AnnotationMetadata importingClassMetadata) {
        return new String[]{"com.mccloud.mccloudtest.conf.Dog","xxx.xxx.xxx.xxx",...};//可以把这里返回的类都加到sprin管理起来
    }
}

@Import(DuckBeanDefinitionRegistrat.class)//可以把一个BeanDefinitionRegistrat注册进来

public class DuckBeanDefinitionRegistrat implements ImportBeanDefinitionRegistrar {
    @Override
    public void registerBeanDefinitions(AnnotationMetadata importingClassMetadata, BeanDefinitionRegistry registry) {
        BeanDefinition beanDefinition = new RootBeanDefinition(Duck.class);
        registry.registerBeanDefinition("Duck", beanDefinition);
    }
}

public class Duck {

    public void gaga(){
        System.out.println("gaga");
    }
}