    001/* ===========================================================
    002 * JFreeChart : a free chart library for the Java(tm) platform
    003 * ===========================================================
    004 *
    005 * (C) Copyright 2000-2011, 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 * [Oracle and Java are registered trademarks of Oracle and/or its affiliates.
    025 * Other names may be trademarks of their respective owners.]
    026 *
    027 * -----------------
    028 * AxisLocation.java
    029 * -----------------
    030 * (C) Copyright 2003-2008, by Object Refinery Limited and Contributors.
    031 *
    032 * Original Author:  David Gilbert (for Object Refinery Limited);
    033 * Contributor(s):   Nick Guenther;
    034 *
    035 * Changes:
    036 * --------
    037 * 02-May-2003 : Version 1 (DG);
    038 * 03-Jul-2003 : Added isTopOrBottom() and isLeftOrRight() methods (DG);
    039 * 13-Aug-2003 : Fixed readResolve() bug (id=788202) (DG);
    040 * 24-Mar-2004 : Added static getOpposite() method (DG);
    041 * ------------- JFREECHART 1.0.x ---------------------------------------------
    042 * 22-Mar-2007 : Added getOpposite() method, suggested by Nick Guenther (DG);
    043 *
    044 */
    045
    046package org.jfree.chart.axis;
    047
    048import java.io.ObjectStreamException;
    049import java.io.Serializable;
    050
    051/**
    052 * Used to indicate the location of an axis on a 2D plot, prior to knowing the
    053 * orientation of the plot.
    054 */
    055public final class AxisLocation implements Serializable {
    056
    057    /** For serialization. */
    058    private static final long serialVersionUID = -3276922179323563410L;
    059
    060    /** Axis at the top or left. */
    061    public static final AxisLocation TOP_OR_LEFT = new AxisLocation(
    062            "AxisLocation.TOP_OR_LEFT");
    063
    064    /** Axis at the top or right. */
    065    public static final AxisLocation TOP_OR_RIGHT = new AxisLocation(
    066            "AxisLocation.TOP_OR_RIGHT");
    067
    068    /** Axis at the bottom or left. */
    069    public static final AxisLocation BOTTOM_OR_LEFT = new AxisLocation(
    070            "AxisLocation.BOTTOM_OR_LEFT");
    071
    072    /** Axis at the bottom or right. */
    073    public static final AxisLocation BOTTOM_OR_RIGHT = new AxisLocation(
    074            "AxisLocation.BOTTOM_OR_RIGHT");
    075
    076    /** The name. */
    077    private String name;
    078
    079    /**
    080     * Private constructor.
    081     *
    082     * @param name  the name.
    083     */
    084    private AxisLocation(String name) {
    085        this.name = name;
    086    }
    087
    088    /**
    089     * Returns the location that is opposite to this location.
    090     *
    091     * @return The opposite location.
    092     *
    093     * @since 1.0.5
    094     */
    095    public AxisLocation getOpposite() {
    096        return getOpposite(this);
    097    }
    098
    099    /**
    100     * Returns a string representing the object.
    101     *
    102     * @return The string.
    103     */
    104    public String toString() {
    105        return this.name;
    106    }
    107
    108    /**
    109     * Returns <code>true</code> if this object is equal to the specified
    110     * object, and <code>false</code> otherwise.
    111     *
    112     * @param obj  the other object (<code>null</code> permitted).
    113     *
    114     * @return A boolean.
    115     */
    116    public boolean equals(Object obj) {
    117
    118        if (this == obj) {
    119            return true;
    120        }
    121        if (!(obj instanceof AxisLocation)) {
    122            return false;
    123        }
    124        AxisLocation location = (AxisLocation) obj;
    125        if (!this.name.equals(location.toString())) {
    126            return false;
    127        }
    128        return true;
    129
    130    }
    131
    132    /**
    133     * Returns the location that is opposite to the supplied location.
    134     *
    135     * @param location  the location (<code>null</code> not permitted).
    136     *
    137     * @return The opposite location.
    138     */
    139    public static AxisLocation getOpposite(AxisLocation location) {
    140        if (location == null) {
    141            throw new IllegalArgumentException("Null 'location' argument.");
    142        }
    143        AxisLocation result = null;
    144        if (location == AxisLocation.TOP_OR_LEFT) {
    145            result = AxisLocation.BOTTOM_OR_RIGHT;
    146        }
    147        else if (location == AxisLocation.TOP_OR_RIGHT) {
    148            result = AxisLocation.BOTTOM_OR_LEFT;
    149        }
    150        else if (location == AxisLocation.BOTTOM_OR_LEFT) {
    151            result = AxisLocation.TOP_OR_RIGHT;
    152        }
    153        else if (location == AxisLocation.BOTTOM_OR_RIGHT) {
    154            result = AxisLocation.TOP_OR_LEFT;
    155        }
    156        else {
    157            throw new IllegalStateException("AxisLocation not recognised.");
    158        }
    159        return result;
    160    }
    161
    162    /**
    163     * Ensures that serialization returns the unique instances.
    164     *
    165     * @return The object.
    166     *
    167     * @throws ObjectStreamException if there is a problem.
    168     */
    169    private Object readResolve() throws ObjectStreamException {
    170        if (this.equals(AxisLocation.TOP_OR_RIGHT)) {
    171            return AxisLocation.TOP_OR_RIGHT;
    172        }
    173        else if (this.equals(AxisLocation.BOTTOM_OR_RIGHT)) {
    174            return AxisLocation.BOTTOM_OR_RIGHT;
    175        }
    176        else if (this.equals(AxisLocation.TOP_OR_LEFT)) {
    177            return AxisLocation.TOP_OR_LEFT;
    178        }
    179        else if (this.equals(AxisLocation.BOTTOM_OR_LEFT)) {
    180            return AxisLocation.BOTTOM_OR_LEFT;
    181        }
    182        return null;
    183    }
    184
    185}