1 /* 2 * Copyright 2002-2006 the original author or authors. 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package org.springframework.web.servlet; 18 19 import java.util.Locale; 20 21 import javax.servlet.http.HttpServletRequest; 22 import javax.servlet.http.HttpServletResponse; 23 24 /** 25 * Interface for web-based locale resolution strategies that allows for 26 * both locale resolution via the request and locale modification via 27 * request and response. 28 * 29 * <p>This interface allows for implementations based on request, session, 30 * cookies, etc. The default implementation is AcceptHeaderLocaleResolver, 31 * simply using the request's locale provided by the respective HTTP header. 32 * 33 * <p>Use <code>RequestContext.getLocale()</code> to retrieve the current locale 34 * in controllers or views, independent of the actual resolution strategy. 35 * 36 * @author Juergen Hoeller 37 * @since 27.02.2003 38 * @see org.springframework.web.servlet.i18n.AcceptHeaderLocaleResolver 39 * @see org.springframework.web.servlet.support.RequestContext#getLocale 40 */ 41 public interface LocaleResolver { 42 43 /** 44 * Resolve the current locale via the given request. 45 * Should return a default locale as fallback in any case. 46 * @param request the request to resolve the locale for 47 * @return the current locale (never <code>null</code>) 48 */ resolveLocale(HttpServletRequest request)49 Locale resolveLocale(HttpServletRequest request); 50 51 /** 52 * Set the current locale to the given one. 53 * @param request the request to be used for locale modification 54 * @param response the response to be used for locale modification 55 * @param locale the new locale, or <code>null</code> to clear the locale 56 * @throws UnsupportedOperationException if the LocaleResolver implementation 57 * does not support dynamic changing of the theme 58 */ setLocale(HttpServletRequest request, HttpServletResponse response, Locale locale)59 void setLocale(HttpServletRequest request, HttpServletResponse response, Locale locale); 60 61 } 62