Java Date to LocalDateTime toLocalDateTime(BigDecimal comTime)

Description

to Local Date Time

License

Open Source License

Declaration

private static LocalDateTime toLocalDateTime(BigDecimal comTime) 

Method Source Code

//package com.java2s;
/*//from ww w.j  av  a  2 s. c o m
 * Copyright (c) 2018 Patrick Scheibe
 * Affiliation: Saxonian Incubator for Clinical Translation, University Leipzig, Germany
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

import java.math.BigDecimal;
import java.math.RoundingMode;

import java.time.LocalDateTime;
import java.time.temporal.ChronoUnit;

public class Main {
    private static final LocalDateTime ZERO_COM_TIME = LocalDateTime.of(1899, 12, 30, 0, 0);
    private static final BigDecimal MILLIS_PER_DAY = new BigDecimal(86400000);

    public static LocalDateTime toLocalDateTime(double d) {
        return toLocalDateTime(BigDecimal.valueOf(d));
    }

    private static LocalDateTime toLocalDateTime(BigDecimal comTime) {
        BigDecimal daysAfterZero = comTime.setScale(0, RoundingMode.DOWN);
        BigDecimal fraction = comTime.subtract(daysAfterZero).abs(); //fraction always represents the time of that day
        BigDecimal fractionMillisAfterZero = fraction.multiply(MILLIS_PER_DAY).setScale(0, RoundingMode.HALF_DOWN);

        return ZERO_COM_TIME.plusDays(daysAfterZero.intValue()).plus(fractionMillisAfterZero.longValue(),
                ChronoUnit.MILLIS);
    }
}

Related

1. toLocalDateTime(Date date)
2. toLocalDateTime(Date date)
3. toLocalDateTime(Date date)
4. toLocalDateTime(Date dateTime)