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Data persistence for repository and validators

In my current program, I must specify in a xml file the class that ensures the data persistence for every entity (repository) and the name of it's validator, and I have this example on how my xml file should look:
<beans>
<bean id="studentService" class="service.StudentService">
<property name="studentRepository" ref="studentRepository"/>
<property name="disciplineRepository" ref="disciplineRepository"/>
<property name="noteRepository" ref="noteRepository"/>
</bean>
<bean id="studentRepository" class="repository.StudentRepository">
<property name="validator" ref="studentValidator"/>
</bean>
<bean id="disciplineRepository" class="repository.DisciplineRepository">
<property name="validator" ref="disciplineValidator"/>
</bean>
<bean id="noteRepository" class="repository.NoteRepository">
<property name="validator" ref="noteValidator"/>
</bean>
<bean id="studentValidator" class="domain.StudentValidator"/>
<bean id="disciplineValidator" class="domain.DisciplineValidator"/>
<bean id="noteValidator" class="domain.NoteValidator"/>
</beans>
My question is, where I can find more information about exactly this kind of implementation, or how does the code to implement this xml file in my program should look?

Configuring locale switching with Spring MVC

First of all I have to say, that I am an absolute beginner in developing Spring Application. What I try to do is to switch the locale from 'en' to 'de'. For this I found the configuration below witch I put in my mvc-dispatcher-servlet.xml
<bean id="messageSource" class="org.springframework.context.support.ResourceBundleMessageSource">
<property name="basename" value="Messages" />
</bean>
<!-- Localization Start -->
<bean id="localeResolver"
class="org.springframework.web.servlet.i18n.SessionLocaleResolver">
<property name="defaultLocale" value="en" />
</bean>
<bean id="localeChangeInterceptor"
class="org.springframework.web.servlet.i18n.LocaleChangeInterceptor">
<property name="paramName" value="language" />
</bean>
<bean class="org.springframework.web.servlet.mvc.support.ControllerClassNameHandlerMapping" >
<property name="interceptors">
<list>
<ref bean="localeChangeInterceptor" />
</list>
</property>
</bean>
After that I expect that I can change the locale by adding '?language=de' behind a existing URL. So the request 'http://localhost:8080/?language=de' should switch the locale. This didn’t work. The website is shown in the defined default language
My property files are located in /src/main/resources. The names are “Messages_en.propperties” and “Messages_de.propperties”. If I switch the default language to “de”, the correct language file is loaded and the website is shown in german.
Has someone an idea what’s wrong in my configuration?

I believe you have to register the LocaleChangeInterceptor with an interceptor in Spring
<!-- Declare the Interceptor -->
<mvc:interceptors>
<bean class="org.springframework.web.servlet.i18n.LocaleChangeInterceptor"
p:paramName="locale" />
</mvc:interceptors>
The LocaleChangeInterceptor is configured to look for the parameter name 'locale' to indicate a change of the user's locale, and is registered as an interceptor using the Spring MVC Namespace. For example, adding 'locale=es' to a URL would change the locale to Spanish.

How to read properties file according to the language just set by the user (in a spring application)

I'm creating a little web application in Spring. I created 2 properties files, italian and english.
With links like IT the user can select the language.
In my file-servlet.xml I have this
......
<bean id="messageSource" class="org.springframework.context.support.ReloadableResourceBundleMessageSource">
<property name="basename" value="classpath:messages" />
<property name="defaultEncoding" value="UTF-8"/>
</bean>
<bean id="localeChangeInterceptor"
class="org.springframework.web.servlet.i18n.LocaleChangeInterceptor">
<property name="paramName" value="lang" />
</bean>
<bean id="localeResolver" class="org.springframework.web.servlet.i18n.CookieLocaleResolver" >
<property name="defaultLocale" value="en"/>
</bean>
<bean id="handlerMapping"
class="org.springframework.web.servlet.mvc.annotation.DefaultAnnotationHandlerMapping">
<property name="interceptors">
<ref bean="localeChangeInterceptor" />
</property>
</bean>
........
I have no problem getting the right value when using <spring:message code="XXX"/>, but i dont understand how to get the right value, according to the language set by the user, when I'm "inside" a class.
I was trying to do something like this :
ApplicationContext context = new ClassPathXmlApplicationContext("messages.xml");
String s = context.getMessage("intestazione",null, Locale.getDefault()));
The problem is that with Locale.getDefault() iI get the Locale of the JVM and not the language set by the user.

You can have the current Locale injected into a controller method by simply declaring it as a parameter. Alternatively you could use LocaleContextHolder.getLocale().

If you can access HttpServletRequest form class, try like this
String s = context.getMessage("intestazione",null, request.getLocale()));

Resolving locale in Spring MVC

I am trying to retrieve locale information in a Java application using this following line of code.
processor = new JQMenusTagProcessor(super.pageContext.getRequest().getLocale());
But the above piece of code always retrieve the default locale i.e en_GB.
How can I retireve the newly changed locale in my application which I am passing along with the url as shown below (as a request)
url?lang=fr
My application-context.xml file looks like as shown below:
<bean id="messageSource"
class="org.springframework.context.support.ReloadableResourceBundleMessageSource">
<property name="basename" value="classpath:messages" />
<property name="defaultEncoding" value="UTF-8"/>
</bean>
<bean id="localeResolver" class="org.springframework.web.servlet.i18n.CookieLocaleResolver">
<property name="cookieName" value="myAppLocaleCookie"/>
<property name="defaultLocale" value="fr" />
<property name="cookieMaxAge" value="604800"/>
<mvc:interceptors>
<bean class="org.springframework.web.servlet.i18n.LocaleChangeInterceptor">
<property name="paramName" value="lang"/>
</bean>
</mvc:interceptors>

How to use Spring's i18n mechanism?

I added localization to my Spring project and it appears to be working but I wonder how I change the language, if the language choice is done based on the browser setting, the HTTP header, a cookie or something else. Is there a way to be explicit as well e.g. taking the locale as a parameter in a way like e.g. hl=de on the HTTP query string? I also want to allow the user to set the language on a settings page, how can I do that? My implementation looks like this and writes messages in English:
<h4 class="title"><fmt:message key="login.title"/></h4>
servlet.xml:
<bean id="messageSource"
class="org.springframework.context.support.ReloadableResourceBundleMessageSource">
<property name="basename" value="classpath:messages" />
<property name="defaultEncoding" value="UTF-8"/>
</bean>
<bean id="localeChangeInterceptor"
class="org.springframework.web.servlet.i18n.LocaleChangeInterceptor">
<property name="paramName" value="lang" />
</bean>
<bean id="localeResolver"
class="org.springframework.web.servlet.i18n.CookieLocaleResolver">
<property name="defaultLocale" value="en"/>
</bean>
<bean id="handlerMapping"
class="org.springframework.web.servlet.mvc.annotation.DefaultAnnotationHandlerMapping">
<property name="interceptors">
<ref bean="localeChangeInterceptor" />
</property>
</bean>
So how can I
a) Make the locale choice explicit by enabling overriding the locale with a HTTP GET parameter such as hl=de for German and hl=fr for French?
b) Let a user choose locale?
Update
The interceptor is not working. The XML is:
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:mvc="http://www.springframework.org/schema/mvc"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.1.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc.xsd">
<bean id="messageSource"
class="org.springframework.context.support.ReloadableResourceBundleMessageSource">
<property name="basename" value="classpath:messages" />
<property name="defaultEncoding" value="UTF-8"/>
</bean>
<bean id="localeResolver" class="org.springframework.web.servlet.i18n.SessionLocaleResolver">
<property name="defaultLocale" value="sv" />
</bean>
<mvc:interceptors>
<bean id="localeChangeInterceptor" class="org.springframework.web.servlet.i18n.LocaleChangeInterceptor">
<property name="paramName" value="language" />
</bean>
</mvc:interceptors>
<bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
<!-- one of the properties available; the maximum file size in bytes -->
<property name="maxUploadSize" value="100000"/>
</bean>
</beans>

a) you defined a bean with id localeChangeInterceptor:
<bean id="localeChangeInterceptor"
class="org.springframework.web.servlet.i18n.LocaleChangeInterceptor">
<property name="paramName" value="lang" />
</bean>
this interceptor enable you to change your locale using the param you choose (in this case: "lang") in your query string (ie: http://mydomain.com/mypage?lang=fr for french)
b) you can provide users link for changing locale using point a)
c) you selected a default locale: "en". otherwhise locale is choosen using browser language
NOTE: you should use <spring:message code="${msg.value}" arguments="${msg.args}"/>for your localized string, not fmt, for more integration with spring...

You already have configured the LocaleChangeInterceptor. Its parameter paramName (you set it to lang) is the request parameter that changed the locale.
change the configuration to hl, then you can use this parameter to change it:
<bean id="localeChangeInterceptor"
class="org.springframework.web.servlet.i18n.LocaleChangeInterceptor">
<property name="paramName" value="hl" />
</bean>
to let the user change the local, you only need to add some link to the page
German
#See JavaDoc: LocalChangeInterceptor#setParamName