Question

在https://github.com/nowszy94/Autowired-null

上重现的步骤

使用BeanDefinitionRegistry:removeBeanDefinition方法从Spring上下文中删除bean后，@Autowired(required = false) spring throws出错：

org.springframework.beans.factory.NoSuchBeanDefinitionException: No bean named 'helloService' is defined
at org.springframework.beans.factory.support.DefaultListableBeanFactory.getBeanDefinition(DefaultListableBeanFactory.java:698) ~[spring-beans-4.2.7.RELEASE.jar:4.2.7.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.getMergedLocalBeanDefinition(AbstractBeanFactory.java:1175) ~[spring-beans-4.2.7.RELEASE.jar:4.2.7.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:284) ~[spring-beans-4.2.7.RELEASE.jar:4.2.7.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:197) ~[spring-beans-4.2.7.RELEASE.jar:4.2.7.RELEASE]
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.resolvedCachedArgument(AutowiredAnnotationBeanPostProcessor.java:508) ~[spring-beans-4.2.7.RELEASE.jar:4.2.7.RELEASE]
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.access$200(AutowiredAnnotationBeanPostProcessor.java:115) ~[spring-beans-4.2.7.RELEASE.jar:4.2.7.RELEASE]
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:538) ~[spring-beans-4.2.7.RELEASE.jar:4.2.7.RELEASE]
at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:88) ~[spring-beans-4.2.7.RELEASE.jar:4.2.7.RELEASE]

Answer 1

在bean创建时发生自动装配。如果您没有定义helloService bean，那么在bean创建期间尝试满足该依赖项时，spring应用程序不会抛出异常。在您的示例中，在将应用程序上下文连接到HelloController bean之后，您将从应用程序上下文中删除它。

删除bean后@Autowired（required = false）失败

1 个答案: