@Conditional

条件装配：满足Conditional指定的条件，则进行组件注入

 

 

@Configuration//告诉springboot这是一个配置类
public class MyConfig {

    @Bean("tom")
    public Stu stu01(){
        return new Stu("汤姆");
    }

    @ConditionalOnBean(name="tom")//当容器中有tom组件时，才会对容器注入user01组件
    @Bean
    public User user01(){
        return new User("张三",20);
    }

}

　

@SpringBootApplication
public class MainApplication {
    public static void main(String[] args) {
        //返回IOC容器
        ConfigurableApplicationContext run = SpringApplication.run(MainApplication.class, args);

        boolean res = run.containsBean("user01");
        System.out.println(res);//true
    }
}