automatically calling another method from a method

[cyber]

is there a way to have a controller method to automatically call a another method.

i am asking this because i am planning to create a base controller where in all extending controller, i need to log some http header for audit and site metrics reports.

example

public BaseController extends MultiActionController{
       public void myAudit(HttpServletRequest request){
                .... code to save my required header info 
                ....like referrer,browser agent,etc to database
       }
}

now my extending class would be like this

public Controller1 extends BaseController{
        public ModelAndView vetsHandler(HttpServletRequest request,       HttpServletResponse response) throws ServletException {
                //i can call myAudit(request) from here
		return new ModelAndView("vetssView");
	}	      
}

as you can see i can call myAudit from the method (programatically) if i want to, but is there a way to call myAudit function automatically whenever a method from the extending class of my BaseController is called. or am I asking too much.

anyway, need suggestion from any expert out there.

thanks.

[ashario]

how about using a servlet filter?

Perhaps subclass org.springframework.web.filter.OncePerRequestFilte r

[cyber]

i believe this will trap all request, i just need to log from my known controller, i.e. BaseController.

is there any way around this?

plus i am also thinking of implementing a simple session-based authentication temporarily while i'm still learning acegi.


thanks for any help.

[simtin]

Hi,

I'd think about an empty (abstract?) method in the BaseController that is called by it after myAudit. All subcontrollers override this method like this:

public BaseController extends MultiActionController{
       public void myAudit(HttpServletRequest request){
                .... code to save my required header info
                ....like referrer,browser agent,etc to database
                vetsHandler(request, ...)
       }

      abstract public <whateverTypeYouNeed> vetsHandler&#40;request, ...&#41; ...
&#125; 

public Controller1 extends BaseController&#123;
        public ModelAndView vetsHandler&#40;HttpServletRequest request,       HttpServletResponse response&#41; throws ServletException &#123;
                
      return new ModelAndView&#40;"vetssView"&#41;;
   &#125;        
&#125;

Regards,
Simon

[cmgharris]

Would a HandlerInterceptor meet your needs here?

[Colin Yates]

Alteratively, look into using AOP. This sounds like an ideal candidate.

(shameless self promotion): AOP scared the c*** out of me until I actually knuckled down and did a small example: http://blogs.warwick.ac.uk/colinyate...ing_aop_rocks/

[cyber]

i've look at HandlerInterceptor, based on the api documentation


A HandlerInterceptor gets called before the appropriate HandlerAdapter triggers the execution of the handler itself. This mechanism can be used for a large field of preprocessing aspects, e.g. for authorization checks, or common handler behavior like locale or theme changes. Its main purpose is to allow for factoring out repetitive handler code.


dont have any experiece using this, can someone show me how.

because i would need the request object from that interceptor and
especially how to assign this to a particular controller only, or any working example or implementation of handling this.

[cmgharris]

In your spring config, split your handler mappings into those that want the interceptor, and those that don't.
Attatch your interceptor to the appropriate mapping:

    <bean id="urlMapping3" class="org.springframework.web.servlet.handler.SimpleUrlHandlerMapping">
        <property name="order"><value>3</value></property>
        <property name="mappings">
            <props>
                <prop key="/appcontrol.bit">appcontrolCtlr</prop>
                <prop key="/upload.bit">uploadCtlr</prop>
                <prop key="/cacheadmin.bit">cacheCtlr</prop>
                <prop key="/paymenttest.bit">paymentTestCtlr</prop>
            </props>
        </property>
        <property name="interceptors">
            <list>
                <ref bean="siteIdInterceptor"/>
                <ref bean="secureInterceptor"/>
                <ref bean="adminJobInterceptor"/>
            </list>
        </property>
    </bean>

Then write your HandlerInterceptor, overriding preHandle and postHandle as required. Both these methods get passed the request (among other things).

HTH

[cyber]

thanks chris, i am confident i can proceed now.