org.springframework.context.i18n.LocaleContextHolder Maven / Gradle / Ivy
/*
* Copyright 2002-2006 the original author or authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.springframework.context.i18n;
import java.util.Locale;
/**
* Simple holder class that associates a LocaleContext instance
* with the current thread. The LocaleContext will be inherited
* by any child threads spawned by the current thread.
*
* Used as a central holder for the current Locale in Spring,
* wherever necessary: for example, in MessageSourceAccessor.
* DispatcherServlet automatically exposes its current Locale here.
* Other applications can expose theirs too, to make classes like
* MessageSourceAccessor automatically use that Locale.
*
* @author Juergen Hoeller
* @since 1.2
* @see LocaleContext
* @see org.springframework.context.support.MessageSourceAccessor
* @see org.springframework.web.servlet.DispatcherServlet
*/
public abstract class LocaleContextHolder {
private static final ThreadLocal localeContextHolder = new ThreadLocal();
private static final ThreadLocal inheritableLocaleContextHolder = new InheritableThreadLocal();
/**
* Reset the LocaleContext for the current thread.
*/
public static void resetLocaleContext() {
localeContextHolder.set(null);
inheritableLocaleContextHolder.set(null);
}
/**
* Associate the given LocaleContext with the current thread,
* not exposing it as inheritable for child threads.
* @param localeContext the current LocaleContext, or null to reset
* the thread-bound context
*/
public static void setLocaleContext(LocaleContext localeContext) {
setLocaleContext(localeContext, false);
}
/**
* Associate the given LocaleContext with the current thread.
* @param localeContext the current LocaleContext, or null to reset
* the thread-bound context
* @param inheritable whether to expose the LocaleContext as inheritable
* for child threads (using an {@link java.lang.InheritableThreadLocal})
*/
public static void setLocaleContext(LocaleContext localeContext, boolean inheritable) {
if (inheritable) {
inheritableLocaleContextHolder.set(localeContext);
localeContextHolder.set(null);
}
else {
localeContextHolder.set(localeContext);
inheritableLocaleContextHolder.set(null);
}
}
/**
* Return the LocaleContext associated with the current thread, if any.
* @return the current LocaleContext, or null if none
*/
public static LocaleContext getLocaleContext() {
LocaleContext localeContext = (LocaleContext) localeContextHolder.get();
if (localeContext == null) {
localeContext = (LocaleContext) inheritableLocaleContextHolder.get();
}
return localeContext;
}
/**
* Associate the given Locale with the current thread.
*
Will implicitly create a LocaleContext for the given Locale,
* not exposing it as inheritable for child threads.
* @param locale the current Locale, or null to reset
* the thread-bound context
* @see SimpleLocaleContext#SimpleLocaleContext(java.util.Locale)
*/
public static void setLocale(Locale locale) {
setLocale(locale, false);
}
/**
* Associate the given Locale with the current thread.
*
Will implicitly create a LocaleContext for the given Locale.
* @param locale the current Locale, or null to reset
* the thread-bound context
* @param inheritable whether to expose the LocaleContext as inheritable
* for child threads (using an {@link java.lang.InheritableThreadLocal})
* @see SimpleLocaleContext#SimpleLocaleContext(java.util.Locale)
*/
public static void setLocale(Locale locale, boolean inheritable) {
LocaleContext localeContext = (locale != null ? new SimpleLocaleContext(locale) : null);
setLocaleContext(localeContext, inheritable);
}
/**
* Return the Locale associated with the current thread, if any,
* or the system default Locale else.
* @return the current Locale, or the system default Locale if no
* specific Locale has been associated with the current thread
* @see LocaleContext#getLocale()
* @see java.util.Locale#getDefault()
*/
public static Locale getLocale() {
LocaleContext localeContext = getLocaleContext();
return (localeContext != null ? localeContext.getLocale() : Locale.getDefault());
}
}