Spring默认BeanName

先说结论：

1、XML配置和注解生成默认BeanName的机制是不同的

2、XML配置默认BeanName = 全类名 + # + 数字，如 com.anyway.p2024.service.impl.BigHouseServiceImpl#0

3、注解默认BeanName = 短类名首字母变成小写，如 bigHouseServiceImpl

注意：如果短类名前2个字母都是大写，则保持短类名不变，比如 ALibaba

示例

com.anyway.p2024.service.BigHouseService

public interface BigHouseService {
}

com.anyway.p2024.service.impl.BigHouseServiceImpl

@Service
public class BigHouseServiceImpl implements BigHouseService {
}

com.anyway.p2024.service.impl.BigHouseServiceImpl2

@Service
public class BigHouseServiceImpl2 implements BigHouseService {
}

com.anyway.p2024.domain.ALibaba

@Component
public class ALibaba {
}

applicationContext.xml

<context:annotation-config />
<context:component-scan base-package="com.anyway" />  

<bean class="com.anyway.p2024.service.impl.BigHouseServiceImpl" />
<bean class="com.anyway.p2024.domain.ALibaba" />
<bean class="com.anyway.p2024.domain.ALibaba" />

Demo04.java

ApplicationContext ac = new ClassPathXmlApplicationContext("classpath:applicationContext.xml");
System.out.println(JSON.toJSON(BeanFactoryUtils.beanNamesForTypeIncludingAncestors(ac, BigHouseService.class)));
System.out.println(JSON.toJSON(BeanFactoryUtils.beanNamesForTypeIncludingAncestors(ac, ALibaba.class)));

输出如下：

["bigHouseServiceImpl","bigHouseServiceImpl2","com.anyway.p2024.service.impl.BigHouseServiceImpl#0"]
["ALibaba","com.anyway.p2024.domain.ALibaba#0","com.anyway.p2024.domain.ALibaba#1"]

思考题：

如果将 com.anyway.p2024.domain.ALibaba 复制到 com.anyway.p2024.service.ALibaba ，执行 Demo04.java 会输出什么？