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@Beanpublic 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}
}
