001    // Copyright 2006, 2009, 2010 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.tapestry5.services;
016    
017    import java.util.List;
018    import java.util.Locale;
019    
020    import org.apache.tapestry5.SelectModel;
021    
022    /**
023     * Sets the thread's locale given a desired locale. Note that the desired locale is just a hint. It will try to honor it
024     * but there is no guarantee that it will be used as is.
025     * <p/>
026     * Localization is controlled by the {@link org.apache.tapestry5.SymbolConstants#SUPPORTED_LOCALES} symbol.
027     */
028    public interface LocalizationSetter
029    {
030        /**
031         * Determines if the provided potential locale name (presumably, extracted from a request URL) is a supported locale
032         * name. A call to this method will always set the {@link org.apache.tapestry5.ioc.services.ThreadLocale} (either
033         * to the provided locale, if supported, or to the default locale). If the locale name is supported, it will also
034         * set the {@link org.apache.tapestry5.services.PersistentLocale} (which may affect how page and event links are
035         * generated, to persist the selected locale across requests).
036         * <p/>
037         * Note that locale names <strong>are</strong> case sensitive.
038         * 
039         * @param localeName
040         *            name of locale to check (which may be blank or not a locale name)
041         * @return true if the locale name is supported and the {@link org.apache.tapestry5.services.PersistentLocale} was
042         *         set
043         * @since 5.1.0.0
044         */
045        boolean setLocaleFromLocaleName(String localeName);
046    
047        /**
048         * Allows the locale to be set from a specified locale name (which may be narrowed or defaulted to a support
049         * locale). Does not set the persistent locale.
050         * 
051         * @param localeName
052         *            locale in effect for this request
053         * @since 5.1.0.0
054         */
055        void setNonPeristentLocaleFromLocaleName(String localeName);
056    
057        /**
058         * Returns a list of supported locales, as per the {@link org.apache.tapestry5.SymbolConstants#SUPPORTED_LOCALES}
059         * symbol.
060         * 
061         * @since 5.2.0
062         */
063        List<Locale> getSupportedLocales();
064    
065        /**
066         * Checks to see if the indicated locale name is a supported locale name (that may have been
067         * incorporated into a request path). This is an important part of
068         * {@linkplain ComponentEventLinkEncoder#decodePageRenderRequest(Request) decoding a request}.
069         * 
070         * @since 5.2.0
071         */
072        boolean isSupportedLocaleName(String localeName);
073    
074        /**
075         * Returns the supported locales packaged as a model. The label for each locale comes from
076         * {@link Locale#getDisplayName(Locale)} (in that locale).
077         * 
078         * @since 5.2.0
079         */
080        SelectModel getSupportedLocalesModel();
081    
082        /**
083         * Converts a locale name into a Locale. The result is cached.
084         * 
085         * @since 5.2.0
086         */
087        Locale toLocale(String localeName);
088    }