    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 * SamplingXYLineRenderer.java
    029 * ---------------------------
    030 * (C) Copyright 2008, 2009, by Object Refinery Limited.
    031 *
    032 * Original Author:  David Gilbert (for Object Refinery Limited);
    033 * Contributor(s):   -;
    034 *
    035 * Changes:
    036 * --------
    037 * 02-Oct-2008 : Version 1 (DG);
    038 * 28-Apr-2009 : Fixed bug in legend shape display, and deprecated
    039 *               getLegendLine() and setLegendLine() - these methods
    040 *               are unnecessary because a mechanism already exists in the
    041 *               superclass for specifying a custom legend shape (DG);
    042 *
    043 */
    044
    045package org.jfree.chart.renderer.xy;
    046
    047import java.awt.Graphics2D;
    048import java.awt.Shape;
    049import java.awt.geom.GeneralPath;
    050import java.awt.geom.Line2D;
    051import java.awt.geom.PathIterator;
    052import java.awt.geom.Rectangle2D;
    053import java.io.IOException;
    054import java.io.ObjectInputStream;
    055import java.io.ObjectOutputStream;
    056import java.io.Serializable;
    057
    058import org.jfree.chart.axis.ValueAxis;
    059import org.jfree.chart.event.RendererChangeEvent;
    060import org.jfree.chart.plot.CrosshairState;
    061import org.jfree.chart.plot.PlotOrientation;
    062import org.jfree.chart.plot.PlotRenderingInfo;
    063import org.jfree.chart.plot.XYPlot;
    064import org.jfree.data.xy.XYDataset;
    065import org.jfree.io.SerialUtilities;
    066import org.jfree.ui.RectangleEdge;
    067import org.jfree.util.PublicCloneable;
    068import org.jfree.util.ShapeUtilities;
    069
    070/**
    071 * A renderer that draws line charts.  The renderer doesn't necessarily plot
    072 * every data item - instead, it tries to plot only those data items that
    073 * make a difference to the visual output (the other data items are skipped).
    074 * This renderer is designed for use with the {@link XYPlot} class.
    075 *
    076 * @since 1.0.13
    077 */
    078public class SamplingXYLineRenderer extends AbstractXYItemRenderer
    079        implements XYItemRenderer, Cloneable, PublicCloneable, Serializable {
    080
    081    /** The shape that is used to represent a line in the legend. */
    082    private transient Shape legendLine;
    083
    084    /**
    085     * Creates a new renderer.
    086     */
    087    public SamplingXYLineRenderer() {
    088        this.legendLine = new Line2D.Double(-7.0, 0.0, 7.0, 0.0);
    089        setBaseLegendShape(this.legendLine);
    090        setTreatLegendShapeAsLine(true);
    091    }
    092
    093    /**
    094     * Returns the shape used to represent a line in the legend.
    095     *
    096     * @return The legend line (never <code>null</code>).
    097     *
    098     * @see #setLegendLine(Shape)
    099     *
    100     * @deprecated As of version 1.0.14, this method is deprecated.  You
    101     * should use the {@link #getBaseLegendShape()} method instead.
    102     */
    103    public Shape getLegendLine() {
    104        return this.legendLine;
    105    }
    106
    107    /**
    108     * Sets the shape used as a line in each legend item and sends a
    109     * {@link RendererChangeEvent} to all registered listeners.
    110     *
    111     * @param line  the line (<code>null</code> not permitted).
    112     *
    113     * @see #getLegendLine()
    114     *
    115     * @deprecated As of version 1.0.14, this method is deprecated.  You should
    116     * use the {@link #setBaseLegendShape(java.awt.Shape)} method instead.
    117     */
    118    public void setLegendLine(Shape line) {
    119        if (line == null) {
    120            throw new IllegalArgumentException("Null 'line' argument.");
    121        }
    122        this.legendLine = line;
    123        fireChangeEvent();
    124    }
    125
    126    /**
    127     * Returns the number of passes through the data that the renderer requires
    128     * in order to draw the chart.  Most charts will require a single pass, but
    129     * some require two passes.
    130     *
    131     * @return The pass count.
    132     */
    133    public int getPassCount() {
    134        return 1;
    135    }
    136
    137    /**
    138     * Records the state for the renderer.  This is used to preserve state
    139     * information between calls to the drawItem() method for a single chart
    140     * drawing.
    141     */
    142    public static class State extends XYItemRendererState {
    143
    144        /** The path for the current series. */
    145        GeneralPath seriesPath;
    146
    147        /**
    148         * A second path that draws vertical intervals to cover any extreme
    149         * values.
    150         */
    151        GeneralPath intervalPath;
    152
    153        /**
    154         * The minimum change in the x-value needed to trigger an update to
    155         * the seriesPath.
    156         */
    157        double dX = 1.0;
    158
    159        /** The last x-coordinate visited by the seriesPath. */
    160        double lastX;
    161
    162        /** The initial y-coordinate for the current x-coordinate. */
    163        double openY = 0.0;
    164
    165        /** The highest y-coordinate for the current x-coordinate. */
    166        double highY = 0.0;
    167
    168        /** The lowest y-coordinate for the current x-coordinate. */
    169        double lowY = 0.0;
    170
    171        /** The final y-coordinate for the current x-coordinate. */
    172        double closeY = 0.0;
    173
    174        /**
    175         * A flag that indicates if the last (x, y) point was 'good'
    176         * (non-null).
    177         */
    178        boolean lastPointGood;
    179
    180        /**
    181         * Creates a new state instance.
    182         *
    183         * @param info  the plot rendering info.
    184         */
    185        public State(PlotRenderingInfo info) {
    186            super(info);
    187        }
    188
    189        /**
    190         * This method is called by the {@link XYPlot} at the start of each
    191         * series pass.  We reset the state for the current series.
    192         *
    193         * @param dataset  the dataset.
    194         * @param series  the series index.
    195         * @param firstItem  the first item index for this pass.
    196         * @param lastItem  the last item index for this pass.
    197         * @param pass  the current pass index.
    198         * @param passCount  the number of passes.
    199         */
    200        public void startSeriesPass(XYDataset dataset, int series,
    201                int firstItem, int lastItem, int pass, int passCount) {
    202            this.seriesPath.reset();
    203            this.intervalPath.reset();
    204            this.lastPointGood = false;
    205            super.startSeriesPass(dataset, series, firstItem, lastItem, pass,
    206                    passCount);
    207        }
    208
    209    }
    210
    211    /**
    212     * Initialises the renderer.
    213     * <P>
    214     * This method will be called before the first item is rendered, giving the
    215     * renderer an opportunity to initialise any state information it wants to
    216     * maintain.  The renderer can do nothing if it chooses.
    217     *
    218     * @param g2  the graphics device.
    219     * @param dataArea  the area inside the axes.
    220     * @param plot  the plot.
    221     * @param data  the data.
    222     * @param info  an optional info collection object to return data back to
    223     *              the caller.
    224     *
    225     * @return The renderer state.
    226     */
    227    public XYItemRendererState initialise(Graphics2D g2,
    228            Rectangle2D dataArea, XYPlot plot, XYDataset data,
    229            PlotRenderingInfo info) {
    230
    231        double dpi = 72;
    232    //        Integer dpiVal = (Integer) g2.getRenderingHint(HintKey.DPI);
    233    //        if (dpiVal != null) {
    234    //            dpi = dpiVal.intValue();
    235    //        }
    236        State state = new State(info);
    237        state.seriesPath = new GeneralPath();
    238        state.intervalPath = new GeneralPath();
    239        state.dX = 72.0 / dpi;
    240        return state;
    241    }
    242
    243    /**
    244     * Draws the visual representation of a single data item.
    245     *
    246     * @param g2  the graphics device.
    247     * @param state  the renderer state.
    248     * @param dataArea  the area within which the data is being drawn.
    249     * @param info  collects information about the drawing.
    250     * @param plot  the plot (can be used to obtain standard color
    251     *              information etc).
    252     * @param domainAxis  the domain axis.
    253     * @param rangeAxis  the range axis.
    254     * @param dataset  the dataset.
    255     * @param series  the series index (zero-based).
    256     * @param item  the item index (zero-based).
    257     * @param crosshairState  crosshair information for the plot
    258     *                        (<code>null</code> permitted).
    259     * @param pass  the pass index.
    260     */
    261    public void drawItem(Graphics2D g2,
    262                         XYItemRendererState state,
    263                         Rectangle2D dataArea,
    264                         PlotRenderingInfo info,
    265                         XYPlot plot,
    266                         ValueAxis domainAxis,
    267                         ValueAxis rangeAxis,
    268                         XYDataset dataset,
    269                         int series,
    270                         int item,
    271                         CrosshairState crosshairState,
    272                         int pass) {
    273
    274        // do nothing if item is not visible
    275        if (!getItemVisible(series, item)) {
    276            return;
    277        }
    278        RectangleEdge xAxisLocation = plot.getDomainAxisEdge();
    279        RectangleEdge yAxisLocation = plot.getRangeAxisEdge();
    280
    281        // get the data point...
    282        double x1 = dataset.getXValue(series, item);
    283        double y1 = dataset.getYValue(series, item);
    284        double transX1 = domainAxis.valueToJava2D(x1, dataArea, xAxisLocation);
    285        double transY1 = rangeAxis.valueToJava2D(y1, dataArea, yAxisLocation);
    286
    287        State s = (State) state;
    288        // update path to reflect latest point
    289        if (!Double.isNaN(transX1) && !Double.isNaN(transY1)) {
    290            float x = (float) transX1;
    291            float y = (float) transY1;
    292            PlotOrientation orientation = plot.getOrientation();
    293            if (orientation == PlotOrientation.HORIZONTAL) {
    294                x = (float) transY1;
    295                y = (float) transX1;
    296            }
    297            if (s.lastPointGood) {
    298                if ((Math.abs(x - s.lastX) > s.dX)) {
    299                    s.seriesPath.lineTo(x, y);
    300                    if (s.lowY < s.highY) {
    301                        s.intervalPath.moveTo((float) s.lastX, (float) s.lowY);
    302                        s.intervalPath.lineTo((float) s.lastX, (float) s.highY);
    303                    }
    304                    s.lastX = x;
    305                    s.openY = y;
    306                    s.highY = y;
    307                    s.lowY = y;
    308                    s.closeY = y;
    309                }
    310                else {
    311                    s.highY = Math.max(s.highY, y);
    312                    s.lowY = Math.min(s.lowY, y);
    313                    s.closeY = y;
    314                }
    315            }
    316            else {
    317                s.seriesPath.moveTo(x, y);
    318                s.lastX = x;
    319                s.openY = y;
    320                s.highY = y;
    321                s.lowY = y;
    322                s.closeY = y;
    323            }
    324            s.lastPointGood = true;
    325        }
    326        else {
    327            s.lastPointGood = false;
    328        }
    329        // if this is the last item, draw the path ...
    330        if (item == s.getLastItemIndex()) {
    331            // draw path
    332            PathIterator pi = s.seriesPath.getPathIterator(null);
    333            int count = 0;
    334            while (!pi.isDone()) {
    335                count++;
    336                pi.next();
    337            }
    338            g2.setStroke(getItemStroke(series, item));
    339            g2.setPaint(getItemPaint(series, item));
    340            g2.draw(s.seriesPath);
    341            g2.draw(s.intervalPath);
    342        }
    343    }
    344
    345    /**
    346     * Returns a clone of the renderer.
    347     *
    348     * @return A clone.
    349     *
    350     * @throws CloneNotSupportedException if the clone cannot be created.
    351     */
    352    public Object clone() throws CloneNotSupportedException {
    353        SamplingXYLineRenderer clone = (SamplingXYLineRenderer) super.clone();
    354        if (this.legendLine != null) {
    355            clone.legendLine = ShapeUtilities.clone(this.legendLine);
    356        }
    357        return clone;
    358    }
    359
    360    /**
    361     * Tests this renderer for equality with an arbitrary object.
    362     *
    363     * @param obj  the object (<code>null</code> permitted).
    364     *
    365     * @return <code>true</code> or <code>false</code>.
    366     */
    367    public boolean equals(Object obj) {
    368        if (obj == this) {
    369            return true;
    370        }
    371        if (!(obj instanceof SamplingXYLineRenderer)) {
    372            return false;
    373        }
    374        if (!super.equals(obj)) {
    375            return false;
    376        }
    377        SamplingXYLineRenderer that = (SamplingXYLineRenderer) obj;
    378        if (!ShapeUtilities.equal(this.legendLine, that.legendLine)) {
    379            return false;
    380        }
    381        return true;
    382    }
    383
    384    /**
    385     * Provides serialization support.
    386     *
    387     * @param stream  the input stream.
    388     *
    389     * @throws IOException  if there is an I/O error.
    390     * @throws ClassNotFoundException  if there is a classpath problem.
    391     */
    392    private void readObject(ObjectInputStream stream)
    393            throws IOException, ClassNotFoundException {
    394        stream.defaultReadObject();
    395        this.legendLine = SerialUtilities.readShape(stream);
    396    }
    397
    398    /**
    399     * Provides serialization support.
    400     *
    401     * @param stream  the output stream.
    402     *
    403     * @throws IOException  if there is an I/O error.
    404     */
    405    private void writeObject(ObjectOutputStream stream) throws IOException {
    406        stream.defaultWriteObject();
    407        SerialUtilities.writeShape(this.legendLine, stream);
    408    }
    409
    410}