Spring dependency injection for Struts Actions

Being used to Spring MVC, I was surprised when I discovered Struts did not use the Action bean I created in the Spring config file when handling web requests. Basically I needed a DAO wired into an existing Struts Action. I created a bean with the appropriate setter for the Struts Action in the Spring config file. However, I got a nasty null pointer exception because the setter was never called.

This should have been obvious if I have given it a thought. The Struts Actions in the web app are managed by Struts, not Spring. To get Spring to perform dependency injection on Struts Actions, you need to use the DelegatingActionProxy.

In the Struts config file

<action path="/store/order" type="org.springframework.web.struts.DelegatingActionProxy" name="orderForm" validate="false">
	<forward name="success" path="/jsp/view.jsp" />
</action>

In the Spring config file

<bean name="/store/order" class="com.whileloop.web.action.OrderAction">
    <property name="basketDao" ref="basketDao"/>
</bean>