001/* ===========================================================
002 * JFreeChart : a free chart library for the Java(tm) platform
003 * ===========================================================
004 *
005 * (C) Copyright 2000-2008, by Object Refinery Limited and Contributors.
006 *
007 * Project Info:  http://www.jfree.org/jfreechart/index.html
008 *
009 * This library is free software; you can redistribute it and/or modify it
010 * under the terms of the GNU Lesser General Public License as published by
011 * the Free Software Foundation; either version 2.1 of the License, or
012 * (at your option) any later version.
013 *
014 * This library is distributed in the hope that it will be useful, but
015 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
016 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
017 * License for more details.
018 *
019 * You should have received a copy of the GNU Lesser General Public
020 * License along with this library; if not, write to the Free Software
021 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
022 * USA.
023 *
024 * [Java is a trademark or registered trademark of Sun Microsystems, Inc.
025 * in the United States and other countries.]
026 *
027 * -------------------
028 * TickUnitSource.java
029 * -------------------
030 * (C) Copyright 2003-2008, by Object Refinery Limited.
031 *
032 * Original Author:  David Gilbert (for Object Refinery Limited);
033 * Contributor(s):   -;
034 *
035 * Changes
036 * -------
037 * 23-Sep-2003 : Version 1 (DG);
038 *
039 */
040
041package org.jfree.chart.axis;
042
043/**
044 * An interface used by the {@link DateAxis} and {@link NumberAxis} classes to
045 * obtain a suitable {@link TickUnit}.
046 */
047public interface TickUnitSource {
048
049    /**
050     * Returns a tick unit that is larger than the supplied unit.
051     *
052     * @param unit   the unit.
053     *
054     * @return A tick unit that is larger than the supplied unit.
055     */
056    public TickUnit getLargerTickUnit(TickUnit unit);
057
058    /**
059     * Returns the tick unit in the collection that is greater than or equal
060     * to (in size) the specified unit.
061     *
062     * @param unit  the unit.
063     *
064     * @return A unit from the collection.
065     */
066    public TickUnit getCeilingTickUnit(TickUnit unit);
067
068    /**
069     * Returns the tick unit in the collection that is greater than or equal
070     * to the specified size.
071     *
072     * @param size  the size.
073     *
074     * @return A unit from the collection.
075     */
076    public TickUnit getCeilingTickUnit(double size);
077
078}