Named constructor args cannot be overridden by child bean definitions [SPR-6463]

[spring-projects-issues]

Jeffrey Sinclair opened SPR-6463 and commented

When I try to override a constructor arg by name in a child bean definition an exception arises which does not arise when I override the constructor arg by index.

I could be mistaken but I see this as a bug because if I can inherit by name and override by index, then I should also be able to override by name.

Specifically I've created an abstract bean definition as follows:

<bean id="abstractPerson" abstract="true">
  <constructor-arg value="Jeff Sinclair" name="name" />     
</bean>

I've then tried to create a concrete bean definition by overriding the named constructor arg:

  <bean id="concretePerson" class="test.spring.Person"
parent="abstractPerson">
    <constructor-arg value="Jeff S Sinclair" name="name" />     
  </bean>

This throws the following exception:

Exception in thread "main" org.springframework.beans.factory.BeanCreationException: 
Error creating bean with name 'concretePerson' defined in class path resource [test/spring/applicationContext.xml]: 
2 constructor arguments specified but no matching constructor found in bean 'concretePerson' 
(hint:specify index/type/name arguments for simple parameters to avoid type ambiguities)
        at
org.springframework.beans.factory.support.ConstructorResolver.autowireConstructor(ConstructorResolver.java:171)
        ...
        at test.spring.Main.main(Main.java:9)   

---

Affects: 3.0 RC2

Issue Links:

• Bean Configuration Overriding [SPR-5509] #10181 Bean Configuration Overriding
• Document constructor-arg 'name' attribute [SPR-7443] #12101 Document constructor-arg 'name' attribute

Referenced from: commits 666700f

[spring-projects-issues]

Jeffrey Sinclair commented

Thought it would be worth referencing #10181 from this JIRA since part of the feature request in #10181 refers to constructor overriding. Of course #10181 is dealing with bean definition overriding rather than bean definition inheritance, however they are a little related.

[spring-projects-issues]

Juergen Hoeller commented

Good point: Even if we're matching constructor argument names somewhat leniently (because they might not be available at runtime, hence the <constructor-arg> name values might be there for descriptive purposes only), it does make sense to allow for them to be overridden by name in child bean definitions.

Juergen