PiecewiseConstantUtils.java

/* ========================================================================
 * PlantUML : a free UML diagram generator
 * ========================================================================
 *
 * (C) Copyright 2009-2024, Arnaud Roques
 *
 * Project Info:  https://plantuml.com
 * 
 * If you like this project or if you find it useful, you can support us at:
 * 
 * https://plantuml.com/patreon (only 1$ per month!)
 * https://plantuml.com/paypal
 * 
 * This file is part of PlantUML.
 *
 * PlantUML is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * PlantUML distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
 * License for more details.
 *
 * You should have received a copy of the GNU General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
 * USA.
 *
 *
 * Original Author:  Arnaud Roques
 * 
 *
 */
package net.sourceforge.plantuml.project.ngm.math;

import java.time.LocalDate;
import java.time.LocalDateTime;
import java.util.Iterator;

public class PiecewiseConstantUtils {

	public static boolean isZeroOnDay(PiecewiseConstant value, LocalDate day) {
		final LocalDateTime startOfDay = day.atStartOfDay();
		final LocalDateTime startOfNextDay = day.plusDays(1).atStartOfDay();

		final Iterator<Segment> iterator = value.iterateSegmentsFrom(startOfDay, TimeDirection.FORWARD);

		while (iterator.hasNext()) {
			final Segment segment = iterator.next();

			if (segment.startExclusive().isBefore(startOfNextDay) == false)
				break;

			if (segment.getValue().isZero() == false)
				return false;

		}

		return true;
	}
}