ResourceBundle.Control implementation based on Liftweb resources XML format

how-to.scala

  // How to use
  def getBundle(locale: Locale): ResourceBundle =
    // this will try to load resource validationMessages.xml
    ResourceBundle.getBundle("validationMessages", locale, LiftResourceBundleControl)

LiftResourceBundleControl.scala

package com.osinka.i18n

import java.util.{Locale,ResourceBundle}
import collection.JavaConversions._
import net.liftweb.common.Box._
import net.liftweb.util.{BundleBuilder,PCDataXmlParser}

/**
 * ResourceBundle.Control implementation for Liftweb resources
 * 
 * Useful if there is a need to use Liftweb localization resources
 * from outside of "S".
 * 
 * @author Alexander Azarov <azarov@osinka.ru>
 * @see java.util.ResourceBundle
 * @see java.util.ResourceBundle.Control
 */
object LiftResourceBundleControl extends ResourceBundle.Control {
  val LiftBundleFormat = "liftweb.xml"
  val Suffix = "xml"

  override def getFormats(baseName: String): java.util.List[String] = LiftBundleFormat :: Nil

  override def newBundle(baseName: String, locale: Locale, fmt: String, loader: ClassLoader, reload: Boolean): ResourceBundle = {
    def resourceName =
      /**
       * We have no need to calculate bundle name (via toBundleName) from baseName and locale, since
       * Lifweb resources file contains all locales at once.
       * 
       * Otherwise, the line below would look like
       * toResourceName(toBundleName(baseName, locale), Suffix)
       */
      toResourceName(baseName, Suffix)

    def stream =
      reload match {
        case true =>
          for {url <- Option(loader getResource resourceName)
               connection <- Option(url.openConnection)}
          yield {
            connection.setUseCaches(false)
            connection.getInputStream
          }

        case false =>
          Option(loader getResourceAsStream resourceName)
      }

    (for {fmt <- Option(fmt) if fmt == LiftBundleFormat
          is <- stream
          xml <- PCDataXmlParser(is)
          b <- BundleBuilder.convert(xml, locale)}
     yield b).orNull
  }
}