Java DateTimeFormatter parseZoneDateTime(String value, DateTimeFormatter formatter)

Description

Workaround for https://bugs.openjdk.java.net/browse/JDK-8066982, which at the moment has only been solved for JDK9.

License

LGPL

Declaration

public static ZonedDateTime parseZoneDateTime(String value, DateTimeFormatter formatter) 

Method Source Code

//package com.java2s;
/*//from ww  w  .  j ava  2s.  com
 * Hibernate Search, full-text search for your domain model
 *
 * License: GNU Lesser General Public License (LGPL), version 2.1 or later
 * See the lgpl.txt file in the root directory or <http://www.gnu.org/licenses/lgpl-2.1.html>.
 */

import java.time.LocalDateTime;
import java.time.ZoneId;
import java.time.ZoneOffset;
import java.time.ZonedDateTime;
import java.time.format.DateTimeFormatter;
import java.time.temporal.ChronoField;
import java.time.temporal.TemporalAccessor;

public class Main {
    /**
     * Workaround for https://bugs.openjdk.java.net/browse/JDK-8066982,
     * which at the moment has only been solved for JDK9.
     *
     * <p>Tested against TCKDTFParsedInstant in
     * http://hg.openjdk.java.net/jdk9/dev/jdk/rev/f371bdfb7875
     * with both JDK8b101 and JDK9 (early access - build 137).
     */
    public static ZonedDateTime parseZoneDateTime(String value, DateTimeFormatter formatter) {
        TemporalAccessor temporal = formatter.parse(value);
        if (!temporal.isSupported(ChronoField.OFFSET_SECONDS)) {
            // No need for a workaround
            return ZonedDateTime.from(temporal);
        }
        /*
         * Rationale
         *
         * The bug lies in the way epoch seconds are retrieved: the date is interpreted as being
         * expressed in the default offset for the timezone, instead of using the given offset.
         * ZonedDateTime.from uses these epoch seconds in priority when retrieving the local date/time,
         * and falls back to using the epoch day and nano of day.
         * We work around the bug by bypassing ZonedDateTime.from and not using the epoch seconds,
         * but instead directly retrieving the LocalDateTime using LocalDateTime.from. This method
         * relies on ChronoField.EPOCH_DAY and ChronoField.NANO_OF_DAY, which (strangely) seem
         * unaffected by the bug.
         */
        ZoneId zone = ZoneId.from(temporal);
        ZoneOffset offset = ZoneOffset.from(temporal);
        LocalDateTime ldt = LocalDateTime.from(temporal);
        return ZonedDateTime.ofInstant(ldt, offset, zone);
    }
}

Related

1. parse(final DateTimeFormatter formatter, final String value, final ZoneId zoneId)
2. parse(String _date, String _format)
3. parse(String format, String datetime)
4. parseAndFormat(String date, DateTimeFormatter fromFormatter, DateTimeFormatter toFormatter)
5. parseDateTime(String dateTimeStr, String format)
6. setDateFormat(String pattern)
7. validateDate(String input, DateTimeFormatter formatter)