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Unit Standard (JSR 363) Reference Implementation.
/**
* Unit-API - Units of Measurement API for Java
* Copyright (c) 2005-2015, Jean-Marie Dautelle, Werner Keil, V2COM.
*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
*
* 3. Neither the name of JSR-363 nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
* THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
* EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
package tec.units.ri.internal.format.l10n;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.Set;
import tec.units.ri.internal.format.TokenException;
/**
* A Java ME compliant backport of {@linkplain java.util.ResourceBundle}
* @author Werner
* @version 0.6
*/
public abstract class L10nResources implements L10nBundle {
protected L10nResources parent;
/**
* Returns a resource bundle using the specified base name and target
* locale.
*/
public static L10nResources getBundle(String baseName, Locale targetLocale) {
L10nResources parentBundle = null;
L10nResources bundle = null;
// Get a list of candidate locales for which resource bundles are
// searched
final List candidateLocales = getCandidateLocales(targetLocale);
// Go through every candidate locale and try to instantiate a
// L10nResources using the base name and the candidate locale
for (int i = candidateLocales.size() - 1; i >= 0; i--) {
Locale locale = candidateLocales.get(i);
// Bundle name consists of the base name plus an underscore and
// locale if there is a locale. Otherwise, it will consist only of
// the base name.
String bundleName = baseName +
((locale.toString().equals("")) ? "" : ("_" + locale));
try {
// Try to instantiate a resource bundle using the name
// constructed above
Class bundleClass = Class.forName(bundleName); // TODO try use generics here
bundle = (L10nResources)bundleClass.newInstance();
// Set the parent bundle for this bundle. For the base bundle
// (the one with the root locale, Locale.ROOT), the parent is
// null.
bundle.setParent(parentBundle);
parentBundle = bundle;
} catch (Exception ex) {
// No need to do anything, just continue to the next bundle
}
}
// If bundle is null even here, no resource bundle could be found.
// This is an error situation.
if (bundle == null) {
throw new TokenException(
"Can't find resource bundle for base name " + baseName + ".");
}
return bundle;
}
/**
* Returns a list of Locales as candidate locales used in bundle
* instantiation.
* @param locale the locale for which a resource bundle is desired
*/
private static List getCandidateLocales(Locale locale) {
String language = locale.getLanguage();
String country = locale.getCountry();
final List locales = new ArrayList(3);
if (!country.equals("")) {
locales.add(locale);
}
if (!language.equals("")) {
locales.add(
(locales.size() == 0) ? locale : new Locale(language, ""));
}
locales.add(Locale.ROOT);
return locales;
}
protected void setParent(L10nResources parent) {
this.parent = parent;
}
public final String getString(String key) {
String string = handleGetString(key);
if (string == null) {
if (parent != null) {
string = parent.getString(key);
}
if (string == null) {
throw new TokenException("Can't find resource for bundle " +
this.getClass().getName() + " and key " + key + ".");
}
}
return string;
}
/**
* Returns a Set of all keys contained in this
* ResourceBundle and its parent bundles.
*
* @return a Set of all keys contained in this
* ResourceBundle and its parent bundles.
*/
public abstract Set keySet();
/**
* Returns an Iterator of the keys contained in
* this ResourceBundle and its parent bundles.
*
* @return an Iterator of the keys contained in
* this ResourceBundle and its parent bundles.
* @see #keySet()
*/
public abstract Iterator getKeys();
/**
* Gets a string for the given key from this resource bundle. Returns null
* if this resource bundle does not contain a string for the given key.
*/
protected abstract String handleGetString(String key);
}