001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017
018package org.apache.commons.lang3.time;
019
020import java.util.TimeZone;
021
022import org.apache.commons.lang3.ObjectUtils;
023
024/**
025 * Helps to deal with {@link java.util.TimeZone}s.
026 *
027 * @since 3.7
028 */
029public class TimeZones {
030
031    /**
032     * A public version of {@link java.util.TimeZone}'s package private {@code GMT_ID} field.
033     */
034    public static final String GMT_ID = "GMT";
035
036    /**
037     * The GMT time zone.
038     *
039     * @since 3.13.0
040     */
041    public static final TimeZone GMT = TimeZone.getTimeZone(GMT_ID);
042
043    /**
044     * Returns the given TimeZone if non-{@code null}, otherwise {@link TimeZone#getDefault()}.
045     *
046     * @param timeZone a locale or {@code null}.
047     * @return the given locale if non-{@code null}, otherwise {@link TimeZone#getDefault()}.
048     * @since 3.13.0
049     */
050    public static TimeZone toTimeZone(final TimeZone timeZone) {
051        return ObjectUtils.getIfNull(timeZone, TimeZone::getDefault);
052    }
053
054    /** Do not instantiate. */
055    private TimeZones() {
056    }
057
058}