accessing Spring MVC DI beans from jsp

Question

Im bit confused so be patient if im trying to do something wrong : -)

In some MVC frameworks you can call controller action from the view if you whish to execute some code and render some partial view. Im not sure what is the correct way to do it in Spring MV

I want to have set of JSP templates. Some of them will be page layouts some of them will be small components like paginator, login box, menu, tag cloud etc etc etc. Each of these component need some beans or controller action to set some data into ViewAndModel so that view could use it.

The problem is i dont want to set all these objects in ecach call. My register controller cares only about regstration processing. So now how do i do it right? how do i call DI beans or controllers from the view to prepare partial views? Or should i create some mappings? or am i approaching the problem from totally wrong angle?

Answer 1

Never access business components from jsp views; something like sitemesh can be used to combine mutiple views in one. Jsps should also not invoke controller methods directly

Answer 2

Spring-MVC can expose the application context's beans to the view layer, if that is what you wish to do.

For example, the InternalResourceViewResolver can be instructed to expose every bean in the context, or just specified ones. Take a look at the exposeContextBeansAsAttributes and exposedContextBeanNames properties.

For example, say you wanted to expose the beans beanA and beanB to your JSPs. You would declare the view resolver in your context thus:

<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
   <property name="exposedContextBeanNames">
      <list>
         <value>beanA</value>
         <value>beanB</value>
      </list>
   </property>
</bean>

Alternatively, to just expose every bean:

<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
   <property name="exposeContextBeansAsAttributes" value="true"/>
</bean>

Whether or not this is a good idea is another question, but Spring does give you the option.