>();
/**
* LocaleUtils instances should NOT be constructed in standard programming.
@@ -143,7 +135,7 @@ public static Locale toLocale(String str) {
*
*
* @param locale the locale to start from
- * @return the unmodifiable list of Locale objects, 0 being locale, never null
+ * @return the unmodifiable list of Locale objects, 0 being locale, not null
*/
public static List localeLookupList(Locale locale) {
return localeLookupList(locale, locale);
@@ -165,7 +157,7 @@ public static List localeLookupList(Locale locale) {
*
* @param locale the locale to start from, null returns empty list
* @param defaultLocale the default locale to use if no other is found
- * @return the unmodifiable list of Locale objects, 0 being locale, never null
+ * @return the unmodifiable list of Locale objects, 0 being locale, not null
*/
public static List localeLookupList(Locale locale, Locale defaultLocale) {
List list = new ArrayList(4);
@@ -195,22 +187,7 @@ public static List localeLookupList(Locale locale, Locale defaultLocale)
* @return the unmodifiable list of available locales
*/
public static List availableLocaleList() {
- if(cAvailableLocaleList == null) {
- initAvailableLocaleList();
- }
- return cAvailableLocaleList;
- }
-
- /**
- * Initializes the availableLocaleList. It is separate from availableLocaleList()
- * to avoid the synchronized block affecting normal use, yet synchronized and
- * lazy loading to avoid a static block affecting other methods in this class.
- */
- private static synchronized void initAvailableLocaleList() {
- if(cAvailableLocaleList == null) {
- List list = Arrays.asList(Locale.getAvailableLocales());
- cAvailableLocaleList = Collections.unmodifiableList(list);
- }
+ return SyncAvoid.AVAILABLE_LOCALE_LIST;
}
//-----------------------------------------------------------------------
@@ -224,21 +201,7 @@ private static synchronized void initAvailableLocaleList() {
* @return the unmodifiable set of available locales
*/
public static Set availableLocaleSet() {
- if(cAvailableLocaleSet == null) {
- initAvailableLocaleSet();
- }
- return cAvailableLocaleSet;
- }
-
- /**
- * Initializes the availableLocaleSet. It is separate from availableLocaleSet()
- * to avoid the synchronized block affecting normal use, yet synchronized and
- * lazy loading to avoid a static block affecting other methods in this class.
- */
- private static synchronized void initAvailableLocaleSet() {
- if(cAvailableLocaleSet == null) {
- cAvailableLocaleSet = Collections.unmodifiableSet( new HashSet(availableLocaleList()) );
- }
+ return SyncAvoid.AVAILABLE_LOCALE_SET;
}
//-----------------------------------------------------------------------
@@ -260,26 +223,26 @@ public static boolean isAvailableLocale(Locale locale) {
* languages available for that country. Variant locales are removed.
*
* @param countryCode the 2 letter country code, null returns empty
- * @return an unmodifiable List of Locale objects, never null
+ * @return an unmodifiable List of Locale objects, not null
*/
public static List languagesByCountry(String countryCode) {
- List langs = cLanguagesByCountry.get(countryCode); //syncd
+ if (countryCode == null) {
+ return Collections.emptyList();
+ }
+ List langs = cLanguagesByCountry.get(countryCode);
if (langs == null) {
- if (countryCode != null) {
- langs = new ArrayList();
- List locales = availableLocaleList();
- for (int i = 0; i < locales.size(); i++) {
- Locale locale = locales.get(i);
- if (countryCode.equals(locale.getCountry()) &&
- locale.getVariant().length() == 0) {
- langs.add(locale);
- }
+ langs = new ArrayList();
+ List locales = availableLocaleList();
+ for (int i = 0; i < locales.size(); i++) {
+ Locale locale = locales.get(i);
+ if (countryCode.equals(locale.getCountry()) &&
+ locale.getVariant().length() == 0) {
+ langs.add(locale);
}
- langs = Collections.unmodifiableList(langs);
- } else {
- langs = Collections.emptyList();
}
- cLanguagesByCountry.put(countryCode, langs); //syncd
+ langs = Collections.unmodifiableList(langs);
+ cLanguagesByCountry.putIfAbsent(countryCode, langs);
+ langs = cLanguagesByCountry.get(countryCode);
}
return langs;
}
@@ -292,29 +255,44 @@ public static List languagesByCountry(String countryCode) {
* countries available for that language. Variant locales are removed.
*
* @param languageCode the 2 letter language code, null returns empty
- * @return an unmodifiable List of Locale objects, never null
+ * @return an unmodifiable List of Locale objects, not null
*/
public static List countriesByLanguage(String languageCode) {
- List countries = cCountriesByLanguage.get(languageCode); //syncd
+ if (languageCode == null) {
+ return Collections.emptyList();
+ }
+ List countries = cCountriesByLanguage.get(languageCode);
if (countries == null) {
- if (languageCode != null) {
- countries = new ArrayList();
- List locales = availableLocaleList();
- for (int i = 0; i < locales.size(); i++) {
- Locale locale = locales.get(i);
- if (languageCode.equals(locale.getLanguage()) &&
- locale.getCountry().length() != 0 &&
- locale.getVariant().length() == 0) {
- countries.add(locale);
- }
+ countries = new ArrayList();
+ List locales = availableLocaleList();
+ for (int i = 0; i < locales.size(); i++) {
+ Locale locale = locales.get(i);
+ if (languageCode.equals(locale.getLanguage()) &&
+ locale.getCountry().length() != 0 &&
+ locale.getVariant().length() == 0) {
+ countries.add(locale);
}
- countries = Collections.unmodifiableList(countries);
- } else {
- countries = Collections.emptyList();
}
- cCountriesByLanguage.put(languageCode, countries); //syncd
+ countries = Collections.unmodifiableList(countries);
+ cCountriesByLanguage.putIfAbsent(languageCode, countries);
+ countries = cCountriesByLanguage.get(languageCode);
}
return countries;
}
+ //-----------------------------------------------------------------------
+ // class to avoid synchronization
+ static class SyncAvoid {
+ /** Unmodifiable list of available locales. */
+ private static List AVAILABLE_LOCALE_LIST;
+ /** Unmodifiable set of available locales. */
+ private static Set AVAILABLE_LOCALE_SET;
+
+ static {
+ List list = new ArrayList(Arrays.asList(Locale.getAvailableLocales())); // extra safe
+ AVAILABLE_LOCALE_LIST = Collections.unmodifiableList(list);
+ AVAILABLE_LOCALE_SET = Collections.unmodifiableSet(new HashSet(availableLocaleList()));
+ }
+ }
+
}