Internationalization in the Java Stack Matt Wheeler

Notes This is a training NOT a presentation Please ask questions Prerequisites – Introduction to Java Stack – Basic Java and XML skills – Installed LdsTech IDE (or other equivalent – good luck there ;)

Overview Internationalization in general Java Internationalization (ResourceBundle) Spring Internationalization (MessageSource) MessageSource vs. ResourceBundle Spring Helpers JSP tags Locale change interceptor Locale resolver

Internationalization in General (I18n) "Internationalization, in relation to computer programming, is the process of designing and writing an application so that it can be used in a global or multinational context. An internationalized program is capable of supporting different languages, as well as date, time, currency, and other values, without software modification.“

Internationalization (continued) "Internationalization is the process of designing software so that it can be adapted (localized) to various languages and regions easily, cost- effectively, and in particular without engineering changes to the software. This generally involves isolating the parts of a program that are dependent on language and culture....“ – j-i18n/section2.html

Localization (L10n) "Localization is the process of adapting a program for use in a specific locale. A locale is a geographic or political region that shares the same language and customs. Localization includes the translation of text such as user interface labels, error messages, and online help. It also includes the culture-specific formatting of data items such as monetary values, times, dates, and numbers."

Localization (continued) "Localization is the process of designing and writing an application capable of dealing with a specific regional, country, language, cultural, business, or political context. In a sense, every application written for a specific area is localized, although most of these effectively support only one locale. Usually, though, true localization is achieved by core code that accesses locale, location, political, or other specific components and modules, along with translating text as appropriate for the audience. A properly internationalized program facilitates and provides a foundation for localization.“ – i18n/section2.html

First Steps of Internationalization Extract translatable text from code Load resources for a specific locale Inject locale specific resources into the application

Java Internationalization (ResourceBundle) ResourceBundle is the basis of Java internationalization – Backed by different data stores Property files (PropertyResourceBundle) Java source code (ListResourceBundle) Represents a collection of key/value pairs for a given locale

For example Property file(s) Accessing the resource ResourceBundle.getBundle("bundle").getString("abc") //some string ResourceBundle.getBundle("bundle", Locale.ITALIAN).getString("abc") //some Italian string #bundle.properties abc=some string #bundle_it.properties abc=some Italian string

DEMO

Spring Internationalization (MessageSource) MessageSource is the root of Spring internationalization MessageSource interface – An abstraction to the actual text store of translated resources Data store can be properties files, database, MarkLogic, … Implement the interface for the given resource store – Implementation of MessageSource can use resource bundles as in native Java

MessageSource Example Place resource bundles in src/main/bundles Configure the message source as follows: classpath:messages classpath:otherbundle

Inject MessageSource Utilize the private MessageSource method=RequestMethod.GET) public void getAStringInCode(ModelMap model) { String message = messageSource.getMessage("abc", null, "default", Locale.US); //do something with message return; }

MessageSource vs. ResourceBundle MessageSource allows all resources to be conglomerated together MessageSource does parameter replacement automatically MessageSource allows for a default (in case message is not found) #born={0} was born on {1}. String pattern = ResourceBundle.getBundle("whatever", Locale.ENGLISH).getString("born"); MessageFormat.format(pattern, "Billy", new Date()) messageSource.getMessage("born", new Object[] {"Billy“, new Date()}, "default", Locale.ENGLISH)

Spring MessageSource taglib ng-framework- reference/html/spring.tld.html#spring.tld.message

DEMO

Spring Internationalization Architecture LocaleResolver – Attempts to determine the current user’s locale – Provides a way to set / cache current user’s locale LocaleChangeInterceptor – Picks up locale changes (from request parameter by default) – Sets locale on the resolver

ChainedLocaleResolver Based on Spring LocaleResolver interface Locale resolution on steroids Sets up multiple locale resolvers from which to determine the user’s locale

ChainedLocaleResolver (configuration) Basic configuration Or when using WAM code.lds.org/maven- sites/stack/module.html?module=web- spring/xsddoc/index.html code.lds.org/maven- sites/stack/module.html?module=web- spring/apidocs/org/lds/stack/web/spring/i18n/ChainedLo caleResolver.html xmlns:stack-web="

Spring MessageSource taglib

Lab 1: Internationalize a page ab_2_Dependency_Injection

Credit where credit is due ials/j-i18n/section2.html