# XYAreaRenderer.java

    /* ===========================================================
     * JFreeChart : a free chart library for the Java(tm) platform
     * ===========================================================
     *
     * (C) Copyright 2000-2007, by Object Refinery Limited and Contributors.
     *
     * Project Info:  http://www.jfree.org/jfreechart/index.html
     *
     * This library is free software; you can redistribute it and/or modify it
     * under the terms of the GNU Lesser General Public License as published by
     * the Free Software Foundation; either version 2.1 of the License, or
     * (at your option) any later version.
     *
     * This library is 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 Lesser General Public
     * License for more details.
     *
     * You should have received a copy of the GNU Lesser 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.
     *
     * [Java is a trademark or registered trademark of Sun Microsystems, Inc.
     * in the United States and other countries.]
     *
     * -------------------
     * XYAreaRenderer.java
     * -------------------
     * (C) Copyright 2002-2007, by Hari and Contributors.
     *
     * Original Author:  Hari (ourhari@hotmail.com);
     * Contributor(s):   David Gilbert (for Object Refinery Limited);
     *                   Richard Atkinson;
     *                   Christian W. Zuckschwerdt;
     *
     * Changes:
     * --------
     * 03-Apr-2002 : Version 1, contributed by Hari.  This class is based on the
     *               StandardXYItemRenderer class (DG);
     * 09-Apr-2002 : Removed the translated zero from the drawItem method -
     *               overridden the initialise() method to calculate it (DG);
     * 30-May-2002 : Added tool tip generator to constructor to match super
     *               class (DG);
     * 25-Jun-2002 : Removed unnecessary local variable (DG);
     * 05-Aug-2002 : Small modification to drawItem method to support URLs for HTML
     *               image maps (RA);
     * 01-Oct-2002 : Fixed errors reported by Checkstyle (DG);
     * 07-Nov-2002 : Renamed AreaXYItemRenderer --> XYAreaRenderer (DG);
     * 25-Mar-2003 : Implemented Serializable (DG);
     * 01-May-2003 : Modified drawItem() method signature (DG);
     * 27-Jul-2003 : Made line and polygon properties protected rather than
     *               private (RA);
     * 30-Jul-2003 : Modified entity constructor (CZ);
     * 20-Aug-2003 : Implemented Cloneable and PublicCloneable (DG);
     * 16-Sep-2003 : Changed ChartRenderingInfo --> PlotRenderingInfo (DG);
     * 07-Oct-2003 : Added renderer state (DG);
     * 08-Dec-2003 : Modified hotspot for chart entity (DG);
     * 10-Feb-2004 : Changed the drawItem() method to make cut-and-paste overriding
     *               easier.  Also moved state class into this class (DG);
     * 25-Feb-2004 : Replaced CrosshairInfo with CrosshairState.  Renamed
     *               XYToolTipGenerator --> XYItemLabelGenerator (DG);
     * 15-Jul-2004 : Switched getX() with getXValue() and getY() with
     *               getYValue() (DG);
     * 11-Nov-2004 : Now uses ShapeUtilities to translate shapes (DG);
     * 19-Jan-2005 : Now accesses primitives only from dataset (DG);
     * 21-Mar-2005 : Override getLegendItem() and equals() methods (DG);
     * 20-Apr-2005 : Use generators for legend tooltips and URLs (DG);
     * ------------- JFREECHART 1.0.x ---------------------------------------------
     * 06-Feb-2007 : Fixed bug 1086307, crosshairs with multiple axes (DG);
     * 14-Feb-2007 : Fixed bug in clone() (DG);
     * 20-Apr-2007 : Updated getLegendItem() for renderer change (DG);
     * 04-May-2007 : Set processVisibleItemsOnly flag to false (DG);
     * 17-May-2007 : Set datasetIndex and seriesIndex in getLegendItem() (DG);
     * 18-May-2007 : Set dataset and seriesKey for LegendItem (DG);
     *
     */

    package org.jfree.chart.renderer.xy;

    import java.awt.Graphics2D;
    import java.awt.Paint;
    import java.awt.Polygon;
    import java.awt.Shape;
    import java.awt.Stroke;
    import java.awt.geom.GeneralPath;
    import java.awt.geom.Line2D;
    import java.awt.geom.Rectangle2D;
    import java.io.IOException;
    import java.io.ObjectInputStream;
    import java.io.ObjectOutputStream;
    import java.io.Serializable;

    import org.jfree.chart.LegendItem;
    import org.jfree.chart.axis.ValueAxis;
    import org.jfree.chart.entity.EntityCollection;
    import org.jfree.chart.event.RendererChangeEvent;
    import org.jfree.chart.labels.XYSeriesLabelGenerator;
    import org.jfree.chart.labels.XYToolTipGenerator;
    import org.jfree.chart.plot.CrosshairState;
    import org.jfree.chart.plot.PlotOrientation;
    import org.jfree.chart.plot.PlotRenderingInfo;
    import org.jfree.chart.plot.XYPlot;
    import org.jfree.chart.urls.XYURLGenerator;
    import org.jfree.data.xy.XYDataset;
    import org.jfree.io.SerialUtilities;
    import org.jfree.util.PublicCloneable;
    import org.jfree.util.ShapeUtilities;

    /**
     * Area item renderer for an {@link XYPlot}.  This class can draw (a) shapes at
     * each point, or (b) lines between points, or (c) both shapes and lines,
     * or (d) filled areas, or (e) filled areas and shapes.
     */
    public class XYAreaRenderer extends AbstractXYItemRenderer
                                implements XYItemRenderer,
                                           Cloneable,
                                           PublicCloneable,
                                           Serializable {

        /** For serialization. */
        private static final long serialVersionUID = -4481971353973876747L;

        /**
         * A state object used by this renderer.
         */
        static class XYAreaRendererState extends XYItemRendererState {

            /** Working storage for the area under one series. */
            public Polygon area;

            /** Working line that can be recycled. */
            public Line2D line;

            /**
             * Creates a new state.
             *
             * @param info  the plot rendering info.
             */
            public XYAreaRendererState(PlotRenderingInfo info) {
                super(info);
                this.area = new Polygon();
                this.line = new Line2D.Double();
            }

        }

        /** Useful constant for specifying the type of rendering (shapes only). */
        public static final int SHAPES = 1;

        /** Useful constant for specifying the type of rendering (lines only). */
        public static final int LINES = 2;

        /**
         * Useful constant for specifying the type of rendering (shapes and lines).
         */
        public static final int SHAPES_AND_LINES = 3;

        /** Useful constant for specifying the type of rendering (area only). */
        public static final int AREA = 4;

        /**
         * Useful constant for specifying the type of rendering (area and shapes).
         */
        public static final int AREA_AND_SHAPES = 5;

        /** A flag indicating whether or not shapes are drawn at each XY point. */
        private boolean plotShapes;

        /** A flag indicating whether or not lines are drawn between XY points. */
        private boolean plotLines;

        /** A flag indicating whether or not Area are drawn at each XY point. */
        private boolean plotArea;

        /** A flag that controls whether or not the outline is shown. */
        private boolean showOutline;

        /**
         * The shape used to represent an area in each legend item (this should
         * never be <code>null</code>).
         */
        private transient Shape legendArea;

        /**
         * Constructs a new renderer.
         */
        public XYAreaRenderer() {
            this(AREA);
        }

        /**
         * Constructs a new renderer.
         *
         * @param type  the type of the renderer.
         */
        public XYAreaRenderer(int type) {
            this(type, null, null);
        }

        /**
         * Constructs a new renderer.  To specify the type of renderer, use one of
         * the constants: <code>SHAPES</code>, <code>LINES</code>,
         * <code>SHAPES_AND_LINES</code>, <code>AREA</code> or
         * <code>AREA_AND_SHAPES</code>.
         *
         * @param type  the type of renderer.
         * @param toolTipGenerator  the tool tip generator to use
         *                          (<code>null</code> permitted).
         * @param urlGenerator  the URL generator (<code>null</code> permitted).
         */
        public XYAreaRenderer(int type, XYToolTipGenerator toolTipGenerator,
                              XYURLGenerator urlGenerator) {

            super();
            setBaseToolTipGenerator(toolTipGenerator);
            setURLGenerator(urlGenerator);

            if (type == SHAPES) {
                this.plotShapes = true;
            }
            if (type == LINES) {
                this.plotLines = true;
            }
            if (type == SHAPES_AND_LINES) {
                this.plotShapes = true;
                this.plotLines = true;
            }
            if (type == AREA) {
                this.plotArea = true;
            }
            if (type == AREA_AND_SHAPES) {
                this.plotArea = true;
                this.plotShapes = true;
            }
            this.showOutline = false;
            GeneralPath area = new GeneralPath();
            area.moveTo(0.0f, -4.0f);
            area.lineTo(3.0f, -2.0f);
            area.lineTo(4.0f, 4.0f);
            area.lineTo(-4.0f, 4.0f);
            area.lineTo(-3.0f, -2.0f);
            area.closePath();
            this.legendArea = area;

        }

        /**
         * Returns true if shapes are being plotted by the renderer.
         *
         * @return <code>true</code> if shapes are being plotted by the renderer.
         */
        public boolean getPlotShapes() {
            return this.plotShapes;
        }

        /**
         * Returns true if lines are being plotted by the renderer.
         *
         * @return <code>true</code> if lines are being plotted by the renderer.
         */
        public boolean getPlotLines() {
            return this.plotLines;
        }

        /**
         * Returns true if Area is being plotted by the renderer.
         *
         * @return <code>true</code> if Area is being plotted by the renderer.
         */
        public boolean getPlotArea() {
            return this.plotArea;
        }

        /**
         * Returns a flag that controls whether or not outlines of the areas are
         * drawn.
         *
         * @return The flag.
         *
         * @see #setOutline(boolean)
         */
        public boolean isOutline() {
            return this.showOutline;
        }

        /**
         * Sets a flag that controls whether or not outlines of the areas are drawn
         * and sends a {@link RendererChangeEvent} to all registered listeners.
         *
         * @param show  the flag.
         *
         * @see #isOutline()
         */
        public void setOutline(boolean show) {
            this.showOutline = show;
            fireChangeEvent();
        }

        /**
         * Returns the shape used to represent an area in the legend.
         *
         * @return The legend area (never <code>null</code>).
         */
        public Shape getLegendArea() {
            return this.legendArea;
        }

        /**
         * Sets the shape used as an area in each legend item and sends a
         * {@link RendererChangeEvent} to all registered listeners.
         *
         * @param area  the area (<code>null</code> not permitted).
         */
        public void setLegendArea(Shape area) {
            if (area == null) {
                throw new IllegalArgumentException("Null 'area' argument.");
            }
            this.legendArea = area;
            fireChangeEvent();
        }

        /**
         * Initialises the renderer and returns a state object that should be
         * passed to all subsequent calls to the drawItem() method.
         *
         * @param g2  the graphics device.
         * @param dataArea  the area inside the axes.
         * @param plot  the plot.
         * @param data  the data.
         * @param info  an optional info collection object to return data back to
         *              the caller.
         *
         * @return A state object for use by the renderer.
         */
        public XYItemRendererState initialise(Graphics2D g2, Rectangle2D dataArea,
                XYPlot plot, XYDataset data, PlotRenderingInfo info) {
            XYAreaRendererState state = new XYAreaRendererState(info);

            // in the rendering process, there is special handling for item
            // zero, so we can't support processing of visible data items only
            state.setProcessVisibleItemsOnly(false);
            return state;
        }

        /**
         * Returns a default legend item for the specified series.  Subclasses
         * should override this method to generate customised items.
         *
         * @param datasetIndex  the dataset index (zero-based).
         * @param series  the series index (zero-based).
         *
         * @return A legend item for the series.
         */
        public LegendItem getLegendItem(int datasetIndex, int series) {
            LegendItem result = null;
            XYPlot xyplot = getPlot();
            if (xyplot != null) {
                XYDataset dataset = xyplot.getDataset(datasetIndex);
                if (dataset != null) {
                    XYSeriesLabelGenerator lg = getLegendItemLabelGenerator();
                    String label = lg.generateLabel(dataset, series);
                    String description = label;
                    String toolTipText = null;
                    if (getLegendItemToolTipGenerator() != null) {
                        toolTipText = getLegendItemToolTipGenerator().generateLabel(
                                dataset, series);
                    }
                    String urlText = null;
                    if (getLegendItemURLGenerator() != null) {
                        urlText = getLegendItemURLGenerator().generateLabel(
                                dataset, series);
                    }
                    Paint paint = lookupSeriesPaint(series);
                    result = new LegendItem(label, description, toolTipText,
                            urlText, this.legendArea, paint);
                    result.setDataset(dataset);
                    result.setDatasetIndex(datasetIndex);
                    result.setSeriesKey(dataset.getSeriesKey(series));
                    result.setSeriesIndex(series);
                }
            }
            return result;
        }

        /**
         * Draws the visual representation of a single data item.
         *
         * @param g2  the graphics device.
         * @param state  the renderer state.
         * @param dataArea  the area within which the data is being drawn.
         * @param info  collects information about the drawing.
         * @param plot  the plot (can be used to obtain standard color information
         *              etc).
         * @param domainAxis  the domain axis.
         * @param rangeAxis  the range axis.
         * @param dataset  the dataset.
         * @param series  the series index (zero-based).
         * @param item  the item index (zero-based).
         * @param crosshairState  crosshair information for the plot
         *                        (<code>null</code> permitted).
         * @param pass  the pass index.
         */
        public void drawItem(Graphics2D g2, XYItemRendererState state,
                Rectangle2D dataArea, PlotRenderingInfo info, XYPlot plot,
                ValueAxis domainAxis, ValueAxis rangeAxis, XYDataset dataset,
                int series, int item, CrosshairState crosshairState, int pass) {

            if (!getItemVisible(series, item)) {
                return;
            }
            XYAreaRendererState areaState = (XYAreaRendererState) state;

            // get the data point...
            double x1 = dataset.getXValue(series, item);
            double y1 = dataset.getYValue(series, item);
            if (Double.isNaN(y1)) {
                y1 = 0.0;
            }
            double transX1 = domainAxis.valueToJava2D(x1, dataArea,
                    plot.getDomainAxisEdge());
            double transY1 = rangeAxis.valueToJava2D(y1, dataArea,
                    plot.getRangeAxisEdge());

            // get the previous point and the next point so we can calculate a
            // "hot spot" for the area (used by the chart entity)...
            int itemCount = dataset.getItemCount(series);
            double x0 = dataset.getXValue(series, Math.max(item - 1, 0));
            double y0 = dataset.getYValue(series, Math.max(item - 1, 0));
            if (Double.isNaN(y0)) {
                y0 = 0.0;
            }
            double transX0 = domainAxis.valueToJava2D(x0, dataArea,
                    plot.getDomainAxisEdge());
            double transY0 = rangeAxis.valueToJava2D(y0, dataArea,
                    plot.getRangeAxisEdge());

            double x2 = dataset.getXValue(series, Math.min(item + 1,
                    itemCount - 1));
            double y2 = dataset.getYValue(series, Math.min(item + 1,
                    itemCount - 1));
            if (Double.isNaN(y2)) {
                y2 = 0.0;
            }
            double transX2 = domainAxis.valueToJava2D(x2, dataArea,
                    plot.getDomainAxisEdge());
            double transY2 = rangeAxis.valueToJava2D(y2, dataArea,
                    plot.getRangeAxisEdge());

            double transZero = rangeAxis.valueToJava2D(0.0, dataArea,
                    plot.getRangeAxisEdge());
            Polygon hotspot = null;
            if (plot.getOrientation() == PlotOrientation.HORIZONTAL) {
                hotspot = new Polygon();
                hotspot.addPoint((int) transZero,
                        (int) ((transX0 + transX1) / 2.0));
                hotspot.addPoint((int) ((transY0 + transY1) / 2.0),
                        (int) ((transX0 + transX1) / 2.0));
                hotspot.addPoint((int) transY1, (int) transX1);
                hotspot.addPoint((int) ((transY1 + transY2) / 2.0),
                        (int) ((transX1 + transX2) / 2.0));
                hotspot.addPoint((int) transZero,
                        (int) ((transX1 + transX2) / 2.0));
            }
            else {  // vertical orientation
                hotspot = new Polygon();
                hotspot.addPoint((int) ((transX0 + transX1) / 2.0),
                        (int) transZero);
                hotspot.addPoint((int) ((transX0 + transX1) / 2.0),
                        (int) ((transY0 + transY1) / 2.0));
                hotspot.addPoint((int) transX1, (int) transY1);
                hotspot.addPoint((int) ((transX1 + transX2) / 2.0),
                        (int) ((transY1 + transY2) / 2.0));
                hotspot.addPoint((int) ((transX1 + transX2) / 2.0),
                        (int) transZero);
            }

            if (item == 0) {  // create a new area polygon for the series
                areaState.area = new Polygon();
                // the first point is (x, 0)
                double zero = rangeAxis.valueToJava2D(0.0, dataArea,
                        plot.getRangeAxisEdge());
                if (plot.getOrientation() == PlotOrientation.VERTICAL) {
                    areaState.area.addPoint((int) transX1, (int) zero);
                }
                else if (plot.getOrientation() == PlotOrientation.HORIZONTAL) {
                    areaState.area.addPoint((int) zero, (int) transX1);
                }
            }

            // Add each point to Area (x, y)
            if (plot.getOrientation() == PlotOrientation.VERTICAL) {
                areaState.area.addPoint((int) transX1, (int) transY1);
            }
            else if (plot.getOrientation() == PlotOrientation.HORIZONTAL) {
                areaState.area.addPoint((int) transY1, (int) transX1);
            }

            PlotOrientation orientation = plot.getOrientation();
            Paint paint = getItemPaint(series, item);
            Stroke stroke = getItemStroke(series, item);
            g2.setPaint(paint);
            g2.setStroke(stroke);

            Shape shape = null;
            if (getPlotShapes()) {
                shape = getItemShape(series, item);
                if (orientation == PlotOrientation.VERTICAL) {
                    shape = ShapeUtilities.createTranslatedShape(shape, transX1,
                            transY1);
                }
                else if (orientation == PlotOrientation.HORIZONTAL) {
                    shape = ShapeUtilities.createTranslatedShape(shape, transY1,
                            transX1);
                }
                g2.draw(shape);
            }

            if (getPlotLines()) {
                if (item > 0) {
                    if (plot.getOrientation() == PlotOrientation.VERTICAL) {
                        areaState.line.setLine(transX0, transY0, transX1, transY1);
                    }
                    else if (plot.getOrientation() == PlotOrientation.HORIZONTAL) {
                        areaState.line.setLine(transY0, transX0, transY1, transX1);
                    }
                    g2.draw(areaState.line);
                }
            }

            // Check if the item is the last item for the series.
            // and number of items > 0.  We can't draw an area for a single point.
            if (getPlotArea() && item > 0 && item == (itemCount - 1)) {

                if (orientation == PlotOrientation.VERTICAL) {
                    // Add the last point (x,0)
                    areaState.area.addPoint((int) transX1, (int) transZero);
                }
                else if (orientation == PlotOrientation.HORIZONTAL) {
                    // Add the last point (x,0)
                    areaState.area.addPoint((int) transZero, (int) transX1);
                }

                g2.fill(areaState.area);

                // draw an outline around the Area.
                if (isOutline()) {
                    g2.setStroke(getItemOutlineStroke(series, item));
                    g2.setPaint(getItemOutlinePaint(series, item));
                    g2.draw(areaState.area);
                }
            }

            int domainAxisIndex = plot.getDomainAxisIndex(domainAxis);
            int rangeAxisIndex = plot.getRangeAxisIndex(rangeAxis);
            updateCrosshairValues(crosshairState, x1, y1, domainAxisIndex,
                    rangeAxisIndex, transX1, transY1, orientation);

            // collect entity and tool tip information...
            EntityCollection entities = state.getEntityCollection();
            if (entities != null && hotspot != null) {
                addEntity(entities, hotspot, dataset, series, item, 0.0, 0.0);
            }

        }

        /**
         * Returns a clone of the renderer.
         *
         * @return A clone.
         *
         * @throws CloneNotSupportedException  if the renderer cannot be cloned.
         */
        public Object clone() throws CloneNotSupportedException {
            XYAreaRenderer clone = (XYAreaRenderer) super.clone();
            clone.legendArea = ShapeUtilities.clone(this.legendArea);
            return clone;
        }

        /**
         * Tests this renderer for equality with an arbitrary object.
         *
         * @param obj  the object (<code>null</code> permitted).
         *
         * @return A boolean.
         */
        public boolean equals(Object obj) {
            if (obj == this) {
                return true;
            }
            if (!(obj instanceof XYAreaRenderer)) {
                return false;
            }
            XYAreaRenderer that = (XYAreaRenderer) obj;
            if (this.plotArea != that.plotArea) {
                return false;
            }
            if (this.plotLines != that.plotLines) {
                return false;
            }
            if (this.plotShapes != that.plotShapes) {
                return false;
            }
            if (this.showOutline != that.showOutline) {
                return false;
            }
            if (!ShapeUtilities.equal(this.legendArea, that.legendArea)) {
                return false;
            }
            return true;
        }

        /**
         * Provides serialization support.
         *
         * @param stream  the input stream.
         *
         * @throws IOException  if there is an I/O error.
         * @throws ClassNotFoundException  if there is a classpath problem.
         */
        private void readObject(ObjectInputStream stream)
                throws IOException, ClassNotFoundException {
            stream.defaultReadObject();
            this.legendArea = SerialUtilities.readShape(stream);
        }

        /**
         * Provides serialization support.
         *
         * @param stream  the output stream.
         *
         * @throws IOException  if there is an I/O error.
         */
        private void writeObject(ObjectOutputStream stream) throws IOException {
            stream.defaultWriteObject();
            SerialUtilities.writeShape(this.legendArea, stream);
        }
    }