Struts2 FileUpload - request is nulled

[Kate Oakes]

Hi!
I have a problem with file upload in Struts2. Everything works fine until I add <interceptor-ref name="fileUpload"/> (even without any parameters) to the action configuration - it results in request being null. If I don't add this line, I get the uploaded file and there aren't any problems with the request. But since I have to restrict what can be uploaded I have to add the interceptor-ref. I use Struts 2.0.11 and Spring 2.5.5. My application also uses Struts 1.2.9 (might this be a problem?).

struts.xml:

<struts>
    ... constants
    
    <!-- w -->
    <package name="vc" extends="json-default">    
        <action name="vpUpdate" method="update" class="pack.VPAction">
            <interceptor-ref name="fileUpload"/>
            <result type="json">
                <param name="includeProperties">
                     success
                </param>
            </result>
        </action>
    </package>
</struts>

Action:

public class VPAction extends CaseAction {
    //... properties / setters
    public String update() throws Exception {
        if(request == null) throw new NullPointerException(); //here something is wrong
        ... logic
        return SUCCESS;
    }
}

CaseAction: (this is my base action)

public abstract class CaseAction extends ActionSupport implements ServletRequestAware, ServletResponseAware, SessionAware {
 
    protected Map session;
 
    protected HttpServletRequest request;
 
    protected HttpServletResponse response;
 
    @Override
    public void setSession(Map session) {
        this.session = session;
    }
 
    @Override
    public void setServletRequest(HttpServletRequest servletRequest) {
        this.request = servletRequest;
    }
 
    @Override
    public void setServletResponse(HttpServletResponse servletResponse) {
        this.response = servletResponse;
    }
}

I would be thankful for any help, or any explanation why this happens, if this is the correct behaviour.
[ July 22, 2008: Message edited by: Kate Oakes ]

[Kate Oakes]

The interceptor reference overrides the default interceptor stack. Adding

<interceptor-ref name="defaultStack" />

in the action configuration in struts.xml solved it.