001    // Copyright 2004, 2005 The Apache Software Foundation
002    //
003    // Licensed under the Apache License, Version 2.0 (the "License");
004    // you may not use this file except in compliance with the License.
005    // You may obtain a copy of the License at
006    //
007    //     http://www.apache.org/licenses/LICENSE-2.0
008    //
009    // Unless required by applicable law or agreed to in writing, software
010    // distributed under the License is distributed on an "AS IS" BASIS,
011    // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
012    // See the License for the specific language governing permissions and
013    // limitations under the License.
014    
015    package org.apache.tapestry.services;
016    
017    import java.util.Locale;
018    
019    /**
020     * Used to determine what is the client-specified locale, if any, for the
021     * current request. This may be stored in the request as an HTTP Cookie, or may
022     * be interpolated from request headers. Additionally, the "raw" value provided
023     * by the client may be filtered down.
024     * 
025     * @author Howard Lewis Ship
026     * @since 4.0
027     */
028    public interface RequestLocaleManager
029    {
030    
031        /**
032         * Determines the locale to use for processing the current request. The
033         * value is returned, but also stored as locale.
034         *
035         * @return The {@link Locale} to be used for this request.
036         */
037    
038        Locale extractLocaleForCurrentRequest();
039    
040        /**
041         * Stores the thread's locale as a cookie for later use.
042         */
043    
044        void persistLocale();
045    }