Spring resolve view name dynamically at runtime based on language - spring

Question

I have a web application where page is displayed in English language. There is a button on header section, clicking on it will change the page to Dutch language. (I will store it in cookie). For this I have to load different JSP, CSS, IMAGE folder. Like, I have below files in folder:
helloPortal.jsp
helloPortal_DU.jsp
I don't want to change each and every Controller class to check for language and set ModelView name accordingly. Instead I will say ModelAndView("helloPortal") and want Spring to do it from InternalResourceViewResolver or some other mechanism.
<beans:bean
class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<beans:property name="prefix" value="/WEB-INF/views/" />
<beans:property name="suffix" value=".jsp" />
</beans:bean> here
I need another ViewResolver where based on language it Suffix _DU.jsp to file name
<beans:bean
class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<beans:property name="prefix" value="/WEB-INF/views/" />
<beans:property name="suffix" value="_DU.jsp" />
</beans:bean>
I googled for this kind of solution but can't find precise solution. InternalResourceViewResolver is for properties file I believe. Is there a way based on cookie/locale change viewName dynamically.
Please let me know if I haven't explained my issue properly.

Answer 1

You could create custom view resolver. The resolver could check the cookies to figure out it needs to resolve to a Dutch version of the view, modify the view name appropriately and then delegate to normal view resolver that you are currently using.
Implementation could look something like this (I haven't tested it, but it should work):
public class DelegatingLocalizedViewResolver implements ViewResolver {
#Autowired
private HttpServletRequest httpServletRequest;
private ViewResolver delegateViewResolver;
#Override
public View resolveViewName(String viewName, Locale locale) throws Exception {
if (isDutchLanguage()) {
return delegateViewResolver.resolveViewName(viewName + "_DU", locale);
}
return delegateViewResolver.resolveViewName(viewName, locale);
}
private boolean isDutchLanguage() {
Cookie[] cookies = httpServletRequest.getCookies();
// ... do cookie logic to figure out if the request is dutch
return true;
}
public void setDelegateViewResolver(ViewResolver delegateViewResolver) {
this.delegateViewResolver = delegateViewResolver;
}
}
XML config would then look something like this:
<beans:bean id="internalResourceViewResolver"
class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<beans:property name="prefix" value="/WEB-INF/views/" />
<beans:property name="suffix" value=".jsp" />
</beans:bean>
<beans:bean class="org.example.DelegatingLocalizedViewResolver">
<beans:property name="delegateViewResolver" ref="internalResourceViewResolver" />
</beans:bean>
PS. You might look into Spring's internationalization / localization support and leverage it instead of storing language in the cookie yourself (especially if you plan to support more languages in the future). Once Spring's localization support is enabled, you will get the country/language information in Locale object in the ViewResolver.