001// Licensed under the Apache License, Version 2.0 (the "License");
002// you may not use this file except in compliance with the License.
003// You may obtain a copy of the License at
004//
005// http://www.apache.org/licenses/LICENSE-2.0
006//
007// Unless required by applicable law or agreed to in writing, software
008// distributed under the License is distributed on an "AS IS" BASIS,
009// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
010// See the License for the specific language governing permissions and
011// limitations under the License.
012
013package org.apache.tapestry5.services;
014
015import java.util.List;
016import java.util.Locale;
017
018import org.apache.tapestry5.SelectModel;
019import org.apache.tapestry5.http.services.Request;
020import org.apache.tapestry5.ioc.annotations.IncompatibleChange;
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 *
026 * Localization is controlled by the {@link org.apache.tapestry5.SymbolConstants#SUPPORTED_LOCALES} symbol.
027 */
028public 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     *
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    @IncompatibleChange(release = "5.4", details = "typo is method name corrected")
056    void setNonPersistentLocaleFromLocaleName(String localeName);
057
058    /**
059     * Allows the locale to be set from the locale of the client as determined from the request headers (which may
060     * be narrowed or defaulted to a supported locale). Does not set the persistent locale.
061     * 
062     * @param request
063     *            incoming request
064     * @since 5.8.3
065     */
066    void setNonPersistentLocaleFromRequest(Request request);
067
068    /**
069     * Returns a list of supported locales, as per the {@link org.apache.tapestry5.SymbolConstants#SUPPORTED_LOCALES}
070     * symbol.
071     * 
072     * @since 5.2.0
073     */
074    List<Locale> getSupportedLocales();
075
076    /**
077     * Checks to see if the indicated locale name is a supported locale name (that may have been
078     * incorporated into a request path). This is an important part of
079     * {@linkplain ComponentEventLinkEncoder#decodePageRenderRequest(Request) decoding a request}.
080     * 
081     * @since 5.2.0
082     */
083    boolean isSupportedLocaleName(String localeName);
084
085    /**
086     * Returns the supported locales packaged as a model. The label for each locale comes from
087     * {@link Locale#getDisplayName(Locale)} (in that locale).
088     * 
089     * @since 5.2.0
090     */
091    SelectModel getSupportedLocalesModel();
092
093    /**
094     * Converts a locale name into a Locale. The result is cached.
095     * 
096     * @since 5.2.0
097     */
098    Locale toLocale(String localeName);
099}