Internationalization

Translations in mangoo I/O are based on the standard Locale of Java.

Locale Determination Order

The Locale is determined in the following order:

Language Parameter in the URL
The language can be specified as either a URL parameter or a query parameter, e.g.:

/my/path?lang=en
/my/path/en

If a URL parameter is used, the URL must be configured accordingly in the Bootstrap class:

On.get().to("/foo/bar/{lang}").respondWith("foobar");

i18n Cookie in the Request
A language preference can be stored in a cookie. You can create such a cookie using the CookieBuilder, e.g.:

public Response localize() {
    Cookie cookie = CookieBuilder.create()
            .name(Default.COOKIE_I18N_NAME.toString())
            .value("en")
            .build();

    return Response.withOk().andCookie(cookie);
}

Accept-Language Header in the Request
The language is determined from the Accept-Language header sent by the client.

Default application language

The application’s default language can be set in the configuration file:

application:
   language: en

Hardcoded Default Value
If no other sources define a language, the application defaults to en.

Accessing Translated Values

mangoo I/O provides a convenient way to access translations by injecting the Messages class.

package controllers;

import com.google.inject.Inject;
import io.mangoo.i18n.Messages;
import io.mangoo.routing.Response;

public class I18nController {

    @Inject
    private Messages messages;

    public Response translation() {
        messages.get("my.translation");
        messages.get("my.othertranslation", "foo");
        ...
    }
}

The Messages class offers two methods for retrieving translations from the resource bundle: with or without optional parameters.

Example resource bundle entries:

my.translation=This is a translation
my.othertranslation=This is a translation with the parameter: {0}

Note

{0} is a placeholder that will be replaced by the passed parameter ("foo").

Translation in Templates

To access translations in a template, use the special i18n tag along with the translation key:

${i18n("my.translation")}

To pass a parameter to the translation, append it to the function call:

${i18n("my.othertranslation", "foo")}

If no matching key is found in the resource bundle, the template will output an empty value.