org.elasticsearch.common.util.LocaleUtils Maven / Gradle / Ivy
/*
* Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
* or more contributor license agreements. Licensed under the Elastic License
* 2.0 and the Server Side Public License, v 1; you may not use this file except
* in compliance with, at your election, the Elastic License 2.0 or the Server
* Side Public License, v 1.
*/
package org.elasticsearch.common.util;
import java.util.Arrays;
import java.util.Locale;
import java.util.MissingResourceException;
/**
* Utilities for for dealing with {@link Locale} objects
*/
public class LocaleUtils {
/**
* Parse the given locale as {@code language}, {@code language-country} or
* {@code language-country-variant}.
* Either underscores or hyphens may be used as separators, but consistently, ie.
* you may not use an hyphen to separate the language from the country and an
* underscore to separate the country from the variant.
* @throws IllegalArgumentException if there are too many parts in the locale string
* @throws IllegalArgumentException if the language or country is not recognized
*/
public static Locale parse(String localeStr) {
boolean useUnderscoreAsSeparator = false;
for (int i = 0; i < localeStr.length(); ++i) {
final char c = localeStr.charAt(i);
if (c == '-') {
// the locale uses - as a separator, as expected
break;
} else if (c == '_') {
useUnderscoreAsSeparator = true;
break;
}
}
final String[] parts;
if (useUnderscoreAsSeparator) {
parts = localeStr.split("_", -1);
} else {
parts = localeStr.split("-", -1);
}
final Locale locale = parseParts(parts);
try {
locale.getISO3Language();
} catch (MissingResourceException e) {
throw new IllegalArgumentException("Unknown language: " + parts[0], e);
}
try {
locale.getISO3Country();
} catch (MissingResourceException e) {
throw new IllegalArgumentException("Unknown country: " + parts[1], e);
}
return locale;
}
private static Locale parseParts(String[] parts) {
switch (parts.length) {
case 3:
// lang, country, variant
return new Locale(parts[0], parts[1], parts[2]);
case 2:
// lang, country
return new Locale(parts[0], parts[1]);
case 1:
if ("ROOT".equalsIgnoreCase(parts[0])) {
return Locale.ROOT;
}
// lang
return new Locale(parts[0]);
default:
throw new IllegalArgumentException(
"Locales can have at most 3 parts but got " + parts.length + ": " + Arrays.asList(parts)
);
}
}
}