    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 * CategoryCrosshairState.java
    029 * ---------------------------
    030 * (C) Copyright 2008, by Object Refinery Limited and Contributors.
    031 *
    032 * Original Author:  David Gilbert (for Object Refinery Limited);
    033 * Contributor(s):   -;
    034 *
    035 * Changes
    036 * -------
    037 * 26-Jun-2008 : Version 1 (DG);
    038 *
    039 */
    040
    041package org.jfree.chart.plot;
    042
    043import java.awt.geom.Point2D;
    044
    045import org.jfree.chart.renderer.category.CategoryItemRenderer;
    046
    047/**
    048 * Represents state information for the crosshairs in a {@link CategoryPlot}.
    049 * An instance of this class is created at the start of the rendering process,
    050 * and updated as each data item is rendered.  At the end of the rendering
    051 * process, this class holds the row key, column key and value for the
    052 * crosshair location.
    053 *
    054 * @since 1.0.11
    055 */
    056public class CategoryCrosshairState extends CrosshairState {
    057
    058    /**
    059     * The row key for the crosshair point.
    060     */
    061    private Comparable rowKey;
    062
    063    /**
    064     * The column key for the crosshair point.
    065     */
    066    private Comparable columnKey;
    067
    068    /**
    069     * Creates a new instance.
    070     */
    071    public CategoryCrosshairState() {
    072        this.rowKey = null;
    073        this.columnKey = null;
    074    }
    075
    076    /**
    077     * Returns the row key.
    078     *
    079     * @return The row key.
    080     */
    081    public Comparable getRowKey() {
    082        return this.rowKey;
    083    }
    084
    085    /**
    086     * Sets the row key.
    087     *
    088     * @param key  the row key.
    089     */
    090    public void setRowKey(Comparable key) {
    091        this.rowKey = key;
    092    }
    093
    094    /**
    095     * Returns the column key.
    096     *
    097     * @return The column key.
    098     */
    099    public Comparable getColumnKey() {
    100        return this.columnKey;
    101    }
    102
    103    /**
    104     * Sets the column key.
    105     *
    106     * @param key  the key.
    107     */
    108    public void setColumnKey(Comparable key) {
    109        this.columnKey = key;
    110    }
    111
    112    /**
    113     * Evaluates a data point from a {@link CategoryItemRenderer} and if it is
    114     * the closest to the anchor point it becomes the new crosshair point.
    115     *
    116     * @param rowKey  the row key.
    117     * @param columnKey  the column key.
    118     * @param value  y coordinate (measured against the range axis).
    119     * @param datasetIndex  the dataset index for this point.
    120     * @param transX  x translated into Java2D space.
    121     * @param transY  y translated into Java2D space.
    122     * @param orientation  the plot orientation.
    123     */
    124    public void updateCrosshairPoint(Comparable rowKey, Comparable columnKey,
    125            double value, int datasetIndex, double transX, double transY,
    126            PlotOrientation orientation) {
    127
    128        Point2D anchor = getAnchor();
    129        if (anchor != null) {
    130            double xx = anchor.getX();
    131            double yy = anchor.getY();
    132            if (orientation == PlotOrientation.HORIZONTAL) {
    133                double temp = yy;
    134                yy = xx;
    135                xx = temp;
    136            }
    137            double d = (transX - xx) * (transX - xx)
    138                    + (transY - yy) * (transY - yy);
    139
    140            if (d < getCrosshairDistance()) {
    141                this.rowKey = rowKey;
    142                this.columnKey = columnKey;
    143                setCrosshairY(value);
    144                setDatasetIndex(datasetIndex);
    145                setCrosshairDistance(d);
    146            }
    147        }
    148
    149    }
    150
    151    /**
    152     * Updates only the crosshair row and column keys (this is for the case
    153     * where the range crosshair does NOT lock onto the nearest data value).
    154     *
    155     * @param rowKey  the row key.
    156     * @param columnKey  the column key.
    157     * @param datasetIndex  the dataset axis index.
    158     * @param transX  the translated x-value.
    159     * @param orientation  the plot orientation.
    160     */
    161    public void updateCrosshairX(Comparable rowKey, Comparable columnKey,
    162            int datasetIndex, double transX, PlotOrientation orientation) {
    163
    164        Point2D anchor = getAnchor();
    165        if (anchor != null) {
    166            double anchorX = anchor.getX();
    167            if (orientation == PlotOrientation.HORIZONTAL) {
    168                anchorX = anchor.getY();
    169            }
    170            double d = Math.abs(transX - anchorX);
    171            if (d < getCrosshairDistance()) {
    172                this.rowKey = rowKey;
    173                this.columnKey = columnKey;
    174                setDatasetIndex(datasetIndex);
    175                setCrosshairDistance(d);
    176            }
    177        }
    178
    179    }
    180
    181}