001/*
002 *  Copyright 2001-2005 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;
019import org.joda.time.DateTimeZone;
020
021/**
022 * Service provider factory for time zones.
023 *
024 * @author Brian S O'Neill
025 * @since 1.0
026 */
027public interface Provider {
028    /**
029     * Retrieves a DateTimeZone for the given id. All providers must at
030     * least support id "UTC".
031     *
032     * @return null if not found
033     */
034    DateTimeZone getZone(String id);
035
036    /**
037     * Returns an unmodifiable set of ids. All providers must at least
038     * support id "UTC".
039     */        
040    Set getAvailableIDs();
041}