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Spring Boot - 扩展接口一览

Spring - BeanFactoryAware扩展接口

org.springframework.beans.factory.BeanNameAware

public interface BeanNameAware extends Aware {

    /**
     * Set the name of the bean in the bean factory that created this bean.
     * <p>Invoked after population of normal bean properties but before an
     * init callback such as {@link InitializingBean#afterPropertiesSet()}
     * or a custom init-method.
     * @param name the name of the bean in the factory.
     * Note that this name is the actual bean name used in the factory, which may
     * differ from the originally specified name: in particular for inner bean
     * names, the actual bean name might have been made unique through appending
     * "#..." suffixes. Use the {@link BeanFactoryUtils#originalBeanName(String)}
     * method to extract the original bean name (without suffix), if desired.
     */
    void setBeanName(String name);

}

触发点&使用场景

触发点在bean的初始化之前，也就是postProcessBeforeInitialization之前，这个类的触发点方法只有一个：setBeanName

使用场景为：用户可以扩展这个点，在初始化bean之前拿到spring容器中注册的的beanName，来自行修改这个beanName的值。

源码分析

org.springframework.context.support.PostProcessorRegistrationDelegate#registerBeanPostProcessors()
    BeanPostProcessor pp = beanFactory.getBean(ppName, BeanPostProcessor.class);
        org.springframework.beans.factory.support.AbstractBeanFactory#getBean
          org.springframework.beans.factory.support.AbstractBeanFactory#doGetBean    
              org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory#createBean
                    org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory#doCreateBean
                         org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory#initializeBean 
                            org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory#invokeAwareMethods

    private void invokeAwareMethods(String beanName, Object bean) {
        if (bean instanceof Aware) {
            if (bean instanceof BeanNameAware) {
                ((BeanNameAware) bean).setBeanName(beanName);
            }
            if (bean instanceof BeanClassLoaderAware) {
                ClassLoader bcl = getBeanClassLoader();
                if (bcl != null) {
                    ((BeanClassLoaderAware) bean).setBeanClassLoader(bcl);
                }
            }
            if (bean instanceof BeanFactoryAware) {
                ((BeanFactoryAware) bean).setBeanFactory(AbstractAutowireCapableBeanFactory.this);
            }
        }
    }

扩展示例

比较简单，随便写一个吧

public class ArtisanBean  implements BeanNameAware{
    public ArtisanBean  () {
        System.out.println("ArtisanBean  init");
    }

    @Override
    public void setBeanName(String name) {
        System.out.println("[BeanNameAware] " + name);
    }
}