Injecting in bean class names

[Paul Newport]

Is it possible to do something like this:

<bean id="transactionManager"
class="${transaction.manager.class}">

.....

</bean>

I want the transaction manager class to be configurable at deployment time, so I want to set the class name from a properties file.

The above doesn't work as it doesn't recognize the fact that I am trying to substitute in a property value.

[karldmoore]

I think your problem here is that the PropertyPlaceholderConfigurer is a BeanFactoryPostProcessor. It's therefore too early in the whole process for this to work.

[Andreas Senft]

As Karl stated, this does not work. However, maybe it's possible to create a proxy class that delegates to a real PlatformTransactionManager and allows for runtime initialization (perhaps based on a properties file or the like).

Regards,
Andreas

[karldmoore]

I was wondering the same thing, wouldn't a ProxyFactoryBean work? Just need to set the targetName dynamically.
http://www.springframework.org/docs/...ctoryBean.html

[Andreas Senft]

I rather thought of a "real" class, because of the dynamic selection.
But if the target name could be set via PropertyPlaceholderConfigurer that should work as well.

Regards,
Andreas

[Paul Newport]

I rather thought of a "real" class, because of the dynamic selection.
But if the target name could be set via PropertyPlaceholderConfigurer that should work as well.

Regards,
Andreas

Thanks for the suggestions - I am reading them honest, just have not have had time to test things out. Basically I want a configurable transaction manager that I can switch depending on whether I am running in a clustered or single node environment, so I want the class of the transaction manager to be soft coded.

[karldmoore]

Wouldn't something like this work?

<bean id="transactionManager" class="org.springframework.aop.framework.ProxyFactoryBean">
    <property name="target">
        <bean class="${transaction.manager">
            <property name="dataSource" ref="dataSource"/>
        </bean>
    </property>
</bean>