Internationalize your seam application

► What is Internationalization?

  In computing, Internationalization (or i18n) can be described as "making your application to be easily adapted to more than one locale".

► How to implement Internationalization in your SEAM project 

   This is not very much difficult. This tutorial will guide you through the steps.

If you open the faces-config.xml file in your WEB-INF folder you will see there are several locales already defined in it as below.

<application>
........
    <locale-config>
      <default-locale>en</default-locale>
      <supported-locale>bg</supported-locale>
      <supported-locale>de</supported-locale>
      <supported-locale>en</supported-locale>
      <supported-locale>fr</supported-locale>
      <supported-locale>tr</supported-locale>
    </locale-config>
</application>

You can add or remove <supported-locale> tags as necessary.

    Now open the resource directory of your web project and you will see the file messages_en.properties. Note the name of the file. Similarly you can create multiple files by naming like messages_<locale>.properties.
These files store texts in various languages, so that when you change the locale, the text is displayed in relevant language.
In this example we are going to show the welcome message in japanese when the user select the Japanese locale.

Let's start...
First add a <supported-locale> tag to the faces-config.xml file which includes japanese locale.
The locale code for Japanese is "ja".  So add
<supported-locale>ja</supported-locale>

Then create the file messages_ja.properties in your resource directory.
Add this line to messages_en.properties file.
welcome_msg=Welcome

Add this line to messages_ja.properties file.
welcome_msg=歓迎

Now what we want is to display the welcome message in English if the locale is en and to display the welcome message in Japanese if the locale is ja.

We are going to use the built-in seam component localeSelector.
Add this code in to your page.

<h:form>
  <h:selectOneMenu value="#{localeSelector.localeString}">
    <f:selectItems value="#{localeSelector.supportedLocales}"/>
    <a4j:support event="onchange" reRender="txtMsg"/>
  </h:selectOneMenu>
  <h:outputText id="txtMsg" value="#{messages.welcome_msg}!"/>
</h:form>

I think it is not necessary to explain what above code does.
Yes, when you select a locale from the combo box it displays the welcome message from the selected language.
Note: You can use #{messages['helloWorld']} instead of #{messages.welcome_msg}. Both give the same result.

See the result...
Save and deploy your application. Open the browser, type the url and go to the page.
Open the combo box and you will see something like this.

Now select the Japanese locale and it should display the message in Japanese language.

Problem....?
Unfortunately you may not get the expected result. You may see something weird like this.

Don't worry. The reason is this.
In .properties  files ISO 8859-1 character encoding is used to encode the input/output stream. Characters which can't be directly represented in this encoding have to be written using Unicode escapes.
So edit your messages_ja.properties file as below.
welcome_msg=\u6B53\u8FCE

Wow... Now you get the desired result.

Note: There are lot of online Unicode escape applications.This is one