001/*
002 *  Copyright 2001-2009 Stephen Colebourne
003 *
004 *  Licensed under the Apache License, Version 2.0 (the "License");
005 *  you may not use this file except in compliance with the License.
006 *  You may obtain a copy of the License at
007 *
008 *      http://www.apache.org/licenses/LICENSE-2.0
009 *
010 *  Unless required by applicable law or agreed to in writing, software
011 *  distributed under the License is distributed on an "AS IS" BASIS,
012 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 *  See the License for the specific language governing permissions and
014 *  limitations under the License.
015 */
016package org.joda.time.tz;
017
018import java.util.Set;
019
020import org.joda.time.DateTimeZone;
021
022/**
023 * Service provider factory for time zones.
024 *
025 * @author Brian S O'Neill
026 * @since 1.0
027 */
028public interface Provider {
029
030    /**
031     * Retrieves a DateTimeZone for the given id. All providers must at
032     * least support id "UTC".
033     *
034     * @return null if not found
035     */
036    DateTimeZone getZone(String id);
037
038    /**
039     * Returns an unmodifiable set of ids. All providers must at least
040     * support id "UTC".
041     */        
042    Set<String> getAvailableIDs();
043
044}