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Overview

The framework supports internationalization (i18n) in the following places:

  1. the UI Tags
  2. Messages and Errors from the ValidationAware interface (implemented by ActionSupport and ValidationAwareSupport)
  3. Within action classes that extend ActionSupport through the getText() method

Resource Bundle Search Order

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For more, see the LocalizedTextUtil class.

Package hierarchy

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Default action's class

If you configure action as follow

<action name="index">
   <result>/index.jsp</result>
</action>

it will use a default class defined with default-class-ref in struts-default.xml which is com.opensymphony.xwork2.ActionSupport. It means you have two options here to get I18N working in that case:

  • define com/opensymphony/xwork2/ActionSupport.properties and put messages there
  • point default-class-ref to your base class and then defined appropriated .properties file (corresponding to class' name or package)

Examples

There are several ways to access the message resources, including getText, the text tag, and the i18n tag.

Using getText from a Tag

To display i18n text, use a call to getText in the property tag, or any other tag, such as the UI tags. (The getText technique is especially useful for labels of UI tags.)

The default implementation of TextProvider which is used in ActionSupport perform evaluation of value read from bundle base on the provided key, see Localizing Output for an example.

Using the text tag

The text tag retrieves a message from the default resource bundle.

Using the I18n tag

The i18n tag pushes an arbitrary resource bundle on to the value stack. Other tags within the scope of the i18n tag can display messages from that resource bundle.

Internationalizing SiteMesh decorators is possible, but there are quirks. See SiteMesh Plugin for more.

Using the Key attribute of UI Tags

The key attribute of most UI tags can be used to retrieve a message from a resource bundle:

<s:textfield key="some.key" name="textfieldName"/>

I18n Interceptor

Essentially, the i18n Interceptor pushes a locale into the ActionContext map upon every request. The framework components that support localization all utilize the ActionContext locale. See I18n Interceptor for details.

Global Resources (struts.custom.i18n.resources) in struts.properties

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Formatting Dates and Numbers

See Formatting Dates and Numbers for more details and examples.

Comparison with Struts 1

Struts 1 users should be familiar with the application.properties resource bundle, where you can put all the messages in the application that are going to be translated. Struts 2, though, splits the resource bundles per action or model class, and you may end up with duplicated messages in those resource bundles. A quick fix for that is to create a file called ActionSupport.properties in com/opensymphony/xwork2 and put it on your classpath. This will only work well if all your actions subclass XWork2's ActionSupport.

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