When Autowiring Spring Beans, a common exception is a BeanCreationException. This means that Spring found a bean to create, but was unable to fulfill the dependencies needed to create this this Spring bean.

Here is an example of a BeanCreationException:

BeanCreationException

Exception in thread "main" org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'helloController': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire method: public void guru.springframework.controllers.HelloController.setHelloWorldService(guru.springframework.services.HelloWorldService); nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type [guru.springframework.services.HelloWorldService] found for dependency: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {}
	at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:334)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1214)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:543)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:482)
	at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:305)
	at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230)
	at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:301)
	at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:196)

There’s actually a number of reasons that will lead to a BeanCreationException when Autowiring beans in Spring. In the video below, I’m going to step through a couple of typical examples.