spring mvc internationalization example

Internationalization (i18n) support in spring mvc example tutorial

 Internationalization is the process of designing a software application so that it can be adapted to various languages and regions without engineering changes. The term is frequently abbreviated as i18n (where 18 stands for the number of letters between the first i and last n in internationalization). Above definition essentially means making changes in your application such that it should be usable in multiple locales (or languages in simple words).

In this Post we will see step by step implementation of Spring with internationalization.

Final Project Structure will look like below:

 

 

Below is the Dependency pom.xml required:

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
  <modelVersion>4.0.0</modelVersion>
  <groupId>com.mahesh.spring</groupId>
  <artifactId>SpringMVCInternationalization</artifactId>
  <packaging>war</packaging>
  <version>1.0-SNAPSHOT</version>
  <name>SpringMVC Maven Webapp</name>
  <url>http://maven.apache.org</url>
  <dependencies>
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>3.8.1</version>
      <scope>test</scope>
    </dependency>
   
    <!-- Spring framework -->
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring</artifactId>
        <version>2.5.6</version>
    </dependency>

    <!-- Spring MVC framework -->
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-webmvc</artifactId>
        <version>2.5.6</version>
    </dependency>
   
    <dependency>
        <groupId>javax.servlet</groupId>
        <artifactId>servlet-api</artifactId>
        <version>2.5</version>
        <scope>provided</scope>
    </dependency>
   
    <!-- JSTL -->
    <dependency>
        <groupId>javax.servlet</groupId>
        <artifactId>jstl</artifactId>
        <version>1.1.2</version>
    </dependency>
   
    <dependency>
        <groupId>taglibs</groupId>
        <artifactId>standard</artifactId>
        <version>1.1.2</version>
    </dependency>

  </dependencies>
  <build>
    <finalName>Spring-webmvc-i18n</finalName>
  </build>
</project>

Below is the code for Controller Class WelcomeController.java 

 

package com.mahesh.web.controller;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.springframework.web.servlet.ModelAndView;
import org.springframework.web.servlet.mvc.AbstractController;

public class WelcomeController extends AbstractController{
   
    protected ModelAndView handleRequestInternal(HttpServletRequest request,
            HttpServletResponse response) throws Exception {

        ModelAndView model = new ModelAndView("WelcomePage");
       
        return model;
    }
   
}

Below is the Spring Configuration file for mvc.dispatcher-servlet.xml

Spring provides following classes for i18n support. Lets see them first:

LocaleChangeInterceptor : This interceptor allows for changing the current locale on every request, via a configurable request parameter. Usually this parameter is lang. So, anytime a user send a request with request parameter “lang=en”, his locale automatically be set as English.
If no parameter has been defined then default parameter name is “locale”.

Register a “LocaleChangeInterceptor” interceptor and reference it to any handler mapping that need to supports the multiple languages. The “paramName” is the parameter value that’s used to set the locale.

SessionLocaleResolver
Register a “SessionLocaleResolver” bean, named it exactly the same characters “localeResolver“. It resolves the locales by getting the predefined attribute from user’s session.

see the full example below:

<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://www.springframework.org/schema/beans
    http://www.springframework.org/schema/beans/spring-beans-2.5.xsd">

    <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>
   
    <!-- Register the bean -->
    <bean class="com.mahesh.web.controller.WelcomeController" />

    <!-- Register the welcome.properties -->
    <bean id="messageSource"
        class="org.springframework.context.support.ResourceBundleMessageSource">
        <property name="basename" value="welcome" />
    </bean>

    <bean id="viewResolver"
        class="org.springframework.web.servlet.view.InternalResourceViewResolver" >
        <property name="prefix">
            <value>/WEB-INF/pages/</value>
        </property>
        <property name="suffix">
            <value>.jsp</value>
        </property>
    </bean>

</beans>

Below is the properties files for different locales

welcome.properties

welcome.message = Happy learning Spring MVC Internationalization

welcome_fr.properties

welcome.message = l'apprentissage heureux Spring MVC Internationalization

Below is the web.xml configuration

<web-app id="WebApp_ID" version="2.4"
    xmlns="http://java.sun.com/xml/ns/j2ee"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee
    http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd">

  <display-name>Spring Web MVC Application</display-name>
 
  <servlet>
      <servlet-name>mvc-dispatcher</servlet-name>
    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
    <load-on-startup>1</load-on-startup>
  </servlet>
 
  <servlet-mapping>
     <servlet-name>mvc-dispatcher</servlet-name>
    <url-pattern>*.htm</url-pattern>
  </servlet-mapping>

    <context-param>
    <param-name>contextConfigLocation</param-name>
    <param-value>/WEB-INF/mvc-dispatcher-servlet.xml</param-value>
  </context-param>
 
  <listener>
    <listener-class>
      org.springframework.web.context.ContextLoaderListener
    </listener-class>
  </listener>
 
</web-app>

Below is the code for JSP Page

<%@ page contentType="text/html;charset=UTF-8" %>
<%@ taglib prefix="spring" uri="http://www.springframework.org/tags" %>
<html>
<body>
<h1>Spring MVC internationalization example</h1>

Language : <a href="?language=en">English</a>|
<a href="?language=fr">French</a>

<h3>
    welcome.message : <spring:message code="welcome.message" text="default text" />
</h3>


Current Locale : ${pageContext.response.locale}

</body>
</html>

Final Step:

generate war file and deploy in tomcat webapps folder and run the application.

OutPut: