1 /* 2 * Copyright 2001-2009 Stephen Colebourne 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 package org.joda.time.tz; 17 18 import java.util.Collections; 19 import java.util.Set; 20 21 import org.joda.time.DateTimeZone; 22 23 /** 24 * Simple time zone provider that supports only UTC. 25 * <p> 26 * UTCProvider is thread-safe and immutable. 27 * 28 * @author Brian S O'Neill 29 * @since 1.0 30 */ 31 public final class UTCProvider implements Provider { 32 33 /** 34 * Constructor. 35 */ 36 public UTCProvider() { 37 super(); 38 } 39 40 /** 41 * Returns {@link DateTimeZone#UTC UTC} for <code>"UTC"</code>, null 42 * otherwise. 43 */ 44 public DateTimeZone getZone(String id) { 45 if ("UTC".equalsIgnoreCase(id)) { 46 return DateTimeZone.UTC; 47 } 48 return null; 49 } 50 51 /** 52 * Returns a singleton collection containing only <code>"UTC"</code>. 53 */ 54 public Set<String> getAvailableIDs() { 55 return Collections.singleton("UTC"); 56 } 57 58 }