001/*
002 * Copyright 2002-2014 the original author or authors.
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 *      https://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 */
016
017package org.springframework.format.datetime.standard;
018
019import java.time.ZoneId;
020import java.time.chrono.Chronology;
021import java.time.format.DateTimeFormatter;
022import java.util.TimeZone;
023
024import org.springframework.context.i18n.LocaleContext;
025import org.springframework.context.i18n.LocaleContextHolder;
026import org.springframework.context.i18n.TimeZoneAwareLocaleContext;
027import org.springframework.lang.UsesJava8;
028
029/**
030 * A context that holds user-specific <code>java.time</code> (JSR-310) settings
031 * such as the user's Chronology (calendar system) and time zone.
032 * A {@code null} property value indicate the user has not specified a setting.
033 *
034 * @author Juergen Hoeller
035 * @since 4.0
036 * @see DateTimeContextHolder
037 */
038@UsesJava8
039public class DateTimeContext {
040
041        private Chronology chronology;
042
043        private ZoneId timeZone;
044
045
046        /**
047         * Set the user's chronology (calendar system).
048         */
049        public void setChronology(Chronology chronology) {
050                this.chronology = chronology;
051        }
052
053        /**
054         * Return the user's chronology (calendar system), if any.
055         */
056        public Chronology getChronology() {
057                return this.chronology;
058        }
059
060        /**
061         * Set the user's time zone.
062         * <p>Alternatively, set a {@link TimeZoneAwareLocaleContext} on
063         * {@link LocaleContextHolder}. This context class will fall back to
064         * checking the locale context if no setting has been provided here.
065         * @see org.springframework.context.i18n.LocaleContextHolder#getTimeZone()
066         * @see org.springframework.context.i18n.LocaleContextHolder#setLocaleContext
067         */
068        public void setTimeZone(ZoneId timeZone) {
069                this.timeZone = timeZone;
070        }
071
072        /**
073         * Return the user's time zone, if any.
074         */
075        public ZoneId getTimeZone() {
076                return this.timeZone;
077        }
078
079
080        /**
081         * Get the DateTimeFormatter with the this context's settings
082         * applied to the base {@code formatter}.
083         * @param formatter the base formatter that establishes default
084         * formatting rules, generally context-independent
085         * @return the contextual DateTimeFormatter
086         */
087        public DateTimeFormatter getFormatter(DateTimeFormatter formatter) {
088                if (this.chronology != null) {
089                        formatter = formatter.withChronology(this.chronology);
090                }
091                if (this.timeZone != null) {
092                        formatter = formatter.withZone(this.timeZone);
093                }
094                else {
095                        LocaleContext localeContext = LocaleContextHolder.getLocaleContext();
096                        if (localeContext instanceof TimeZoneAwareLocaleContext) {
097                                TimeZone timeZone = ((TimeZoneAwareLocaleContext) localeContext).getTimeZone();
098                                if (timeZone != null) {
099                                        formatter = formatter.withZone(timeZone.toZoneId());
100                                }
101                        }
102                }
103                return formatter;
104        }
105
106}