ref local does not preserve local bean definitions ?

[snwiem]

Hi all,

i've an questing concerning application context definitions.

Suggest the following project setup.

Bean1: test1.MyBean
Bean2: test2.MyBean
Bean3: test3.UserA
Bean4: test3.UserB

There are two bean factory definitions (as xml)
context-a.xml:

<bean id="MyBean" class="test1.MyBean"/>
	
<bean id="UserA" class="test3.UserA">
	<property name="bean">
		<ref local="MyBean"/>
	</property>
</bean>

context-b.xml

<bean id="MyBean" class="test2.MyBean"/>
	
<bean id="UserB" class="test3.UserB">
	<property name="bean">
		<ref local="MyBean"/>
	</property>
</bean>

The ApplicationContext is loaded using the following code:

this.applicationContext = new ClassPathXmlApplicationContext(
	new String[]{
		"context-a.xml",
		"context-b.xml"
	}
);

On context initialization spring gives me the following exception:

Exception in thread "main" org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'UserA' defined in class path resource [context-a.xml]: Error setting property values; nested exception is org.springframework.beans.PropertyAccessExceptionsException: PropertyAccessExceptionsException (1 errors); nested propertyAccessExceptions are: [org.springframework.beans.TypeMismatchException: Failed to convert property value of type [test2.MyBean] to required type [test1.MyBean] for property 'bean']
PropertyAccessExceptionsException (1 errors)
org.springframework.beans.TypeMismatchException: Failed to convert property value of type [test2.MyBean] to required type [test1.MyBean] for property 'bean'

Enabling the debug logging is could see:

INFO  org.springframework.beans.factory.support.DefaultListableBeanFactory - Overriding bean definition for bean 'MyBean': replacing [Root bean: class [test1.MyBean]; abstract=false; singleton=true; lazyInit=false; autowire=0; dependencyCheck=0; factoryBeanName=null; factoryMethodName=null; initMethodName=null; destroyMethodName=null; defined in class path resource [context-a.xml]] with [Root bean: class [test2.MyBean]; abstract=false; singleton=true; lazyInit=false; autowire=0; dependencyCheck=0; factoryBeanName=null; factoryMethodName=null; initMethodName=null; destroyMethodName=null; defined in class path resource [context-b.xml]]

My question is, why the 'ref local' definition does not use the local bean definition per context.
Is there a way (beside just renaming the booth MyBean-definitions to unique names) to force the BeanFactory to use the local bean references ?

Greets and Thanx for your suggestions
Sebastian Wiemer

[Andreas Senft]

I also encountered this behavior before. The point is, that ref-local just ensures on xml level that the referenced entity exists, while a normal ref could fail only on a real access at runtime.
When overriding a referenced entity it is still existing, so the contract of ref-local still holds. ref-local was (afaik) never intended to prevent overriding.

As for preventing overriding in general, see the "allowBeanDefinitionOverriding" property of DefaultListableBeanFactory.

Regards,
Andreas

[snwiem]

The 'allowBeanDefinitionOverriding' on DefaultListableBeanFactory works
as expected.

Unforunately i'm using spring witin a web container loading the bean definition files using the ContextLoaderListener.

I couldn't find a solution to set the allowBeanDefinitionOverwriting having a look in the documentation, source code and dtd definition.

So is it true, that i have to implement my own XmlWebApplicationContext class and configure it withing the ContextLoader.properties file in spring.jar ?!?


Would be nice to see any other solutions.

greets
Sebastian Wiemer

[Andreas Senft]

At least I do not know about an alternative solution to the one you already came up with (using a subclass).

Regards,
Andreas