/* ===========================================================
 * JFreeChart : a free chart library for the Java(tm) platform
 * ===========================================================
 *
 * (C) Copyright 2000-2005, 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA.
 *
 * [Java is a trademark or registered trademark of Sun Microsystems, Inc. 
 * in the United States and other countries.]
 *
 * ---------------------------------
 * AbstractCategoryItemRenderer.java
 * ---------------------------------
 * (C) Copyright 2002-2005, by Object Refinery Limited.
 *
 * Original Author:  David Gilbert (for Object Refinery Limited);
 * Contributor(s):   Richard Atkinson;
 *
 * $Id: AbstractCategoryItemRenderer.java,v 1.12 2005/03/08 15:53:25 mungady Exp $
 *
 * Changes:
 * --------
 * 29-May-2002 : Version 1 (DG);
 * 06-Jun-2002 : Added accessor methods for the tool tip generator (DG);
 * 11-Jun-2002 : Made constructors protected (DG);
 * 26-Jun-2002 : Added axis to initialise method (DG);
 * 05-Aug-2002 : Added urlGenerator member variable plus accessors (RA);
 * 22-Aug-2002 : Added categoriesPaint attribute, based on code submitted by 
 *               Janet Banks.  This can be used when there is only one series, 
 *               and you want each category item to have a different color (DG);
 * 01-Oct-2002 : Fixed errors reported by Checkstyle (DG);
 * 29-Oct-2002 : Fixed bug where background image for plot was not being 
 *               drawn (DG);
 * 05-Nov-2002 : Replaced references to CategoryDataset with TableDataset (DG);
 * 26-Nov 2002 : Replaced the isStacked() method with getRangeType() (DG);
 * 09-Jan-2003 : Renamed grid-line methods (DG);
 * 17-Jan-2003 : Moved plot classes into separate package (DG);
 * 25-Mar-2003 : Implemented Serializable (DG);
 * 12-May-2003 : Modified to take into account the plot orientation (DG);
 * 12-Aug-2003 : Very minor javadoc corrections (DB)
 * 13-Aug-2003 : Implemented Cloneable (DG);
 * 16-Sep-2003 : Changed ChartRenderingInfo --> PlotRenderingInfo (DG);
 * 05-Nov-2003 : Fixed marker rendering bug (833623) (DG);
 * 21-Jan-2004 : Update for renamed method in ValueAxis (DG);
 * 11-Feb-2004 : Modified labelling for markers (DG);
 * 12-Feb-2004 : Updated clone() method (DG);
 * 15-Apr-2004 : Created a new CategoryToolTipGenerator interface (DG);
 * 05-May-2004 : Fixed bug (948310) where interval markers extend outside axis 
 *               range (DG);
 * 14-Jun-2004 : Fixed bug in drawRangeMarker() method - now uses 'paint' and 
 *               'stroke' rather than 'outlinePaint' and 'outlineStroke' (DG);
 * 15-Jun-2004 : Interval markers can now use GradientPaint (DG);
 * 30-Sep-2004 : Moved drawRotatedString() from RefineryUtilities 
 *               --> TextUtilities (DG);
 * 01-Oct-2004 : Fixed bug 1029697, problem with label alignment in 
 *               drawRangeMarker() method (DG);
 * 07-Jan-2005 : Renamed getRangeExtent() --> findRangeBounds() (DG);
 * 21-Jan-2005 : Modified return type of calculateRangeMarkerTextAnchorPoint() 
 *               method (DG);
 * 08-Mar-2005 : Fixed positioning of marker labels (DG);
 * 
 */

package org.jfree.chart.renderer.category;

import java.awt.Font;
import java.awt.GradientPaint;
import java.awt.Graphics2D;
import java.awt.Paint;
import java.awt.Shape;
import java.awt.Stroke;
import java.awt.geom.Line2D;
import java.awt.geom.Point2D;
import java.awt.geom.Rectangle2D;
import java.io.Serializable;

import org.jfree.chart.LegendItem;
import org.jfree.chart.LegendItemCollection;
import org.jfree.chart.axis.CategoryAxis;
import org.jfree.chart.axis.ValueAxis;
import org.jfree.chart.event.RendererChangeEvent;
import org.jfree.chart.labels.CategoryLabelGenerator;
import org.jfree.chart.labels.CategoryToolTipGenerator;
import org.jfree.chart.labels.ItemLabelPosition;
import org.jfree.chart.plot.CategoryPlot;
import org.jfree.chart.plot.DrawingSupplier;
import org.jfree.chart.plot.IntervalMarker;
import org.jfree.chart.plot.Marker;
import org.jfree.chart.plot.PlotOrientation;
import org.jfree.chart.plot.PlotRenderingInfo;
import org.jfree.chart.plot.ValueMarker;
import org.jfree.chart.renderer.AbstractRenderer;
import org.jfree.chart.urls.CategoryURLGenerator;
import org.jfree.data.Range;
import org.jfree.data.category.CategoryDataset;
import org.jfree.data.general.DatasetUtilities;
import org.jfree.text.TextUtilities;
import org.jfree.ui.GradientPaintTransformer;
import org.jfree.ui.LengthAdjustmentType;
import org.jfree.ui.RectangleAnchor;
import org.jfree.ui.RectangleInsets;
import org.jfree.util.ObjectList;
import org.jfree.util.ObjectUtilities;
import org.jfree.util.PublicCloneable;

/**
 * An abstract base class that you can use to implement a new 
 * {@link CategoryItemRenderer}.  When you create a new 
 * {@link CategoryItemRenderer} you are not required to extend this class,
 * but it makes the job easier.
 */
public abstract class AbstractCategoryItemRenderer extends AbstractRenderer
    implements CategoryItemRenderer, Cloneable, PublicCloneable, Serializable {

    /** The plot that the renderer is assigned to. */
    private CategoryPlot plot;

    /** The label generator for ALL series. */
    private CategoryLabelGenerator labelGenerator;

    /** A list of item label generators (one per series). */
    private ObjectList labelGeneratorList;

    /** The base item label generator. */
    private CategoryLabelGenerator baseLabelGenerator;

    /** The tool tip generator for ALL series. */
    private CategoryToolTipGenerator toolTipGenerator;

    /** A list of tool tip generators (one per series). */
    private ObjectList toolTipGeneratorList;

    /** The base tool tip generator. */
    private CategoryToolTipGenerator baseToolTipGenerator;

    /** The URL generator. */
    private CategoryURLGenerator itemURLGenerator;

    /** A list of item label generators (one per series). */
    private ObjectList itemURLGeneratorList;

    /** The base item label generator. */
    private CategoryURLGenerator baseItemURLGenerator;

    /** The number of rows in the dataset (temporary record). */
    private transient int rowCount;

    /** The number of columns in the dataset (temporary record). */
    private transient int columnCount;

    /**
     * Creates a new renderer with no tool tip generator and no URL generator.
     * The defaults (no tool tip or URL generators) have been chosen to 
     * minimise the processing required to generate a default chart.  If you 
     * require tool tips or URLs, then you can easily add the required 
     * generators.
     */
    protected AbstractCategoryItemRenderer() {
        this.labelGenerator = null;
        this.labelGeneratorList = new ObjectList();
        this.toolTipGenerator = null;
        this.toolTipGeneratorList = new ObjectList();
        this.itemURLGenerator = null;
        this.itemURLGeneratorList = new ObjectList();
    }
    
    /**
     * Returns the number of passes through the dataset required by the 
     * renderer.  This method returns <code>1</code>, subclasses should 
     * override if they need more passes.
     * 
     * @return The pass count.
     */
    public int getPassCount() {
        return 1;
    }

    /**
     * Returns the plot that the renderer has been assigned to (where 
     * <code>null</code> indicates that the renderer is not currently assigned 
     * to a plot).
     *
     * @return The plot (possibly <code>null</code>).
     */
    public CategoryPlot getPlot() {
        return this.plot;
    }

    /**
     * Sets the plot that the renderer has been assigned to.  This method is 
     * usually called by the {@link CategoryPlot}, in normal usage you 
     * shouldn't need to call this method directly.
     *
     * @param plot  the plot (<code>null</code> not permitted).
     */
    public void setPlot(CategoryPlot plot) {
        if (plot == null) {
            throw new IllegalArgumentException("Null 'plot' argument.");   
        }
        this.plot = plot;
    }
    
    // LABEL GENERATOR

    /**
     * Returns the label generator for a data item.  This implementation simply
     * passes control to the {@link #getSeriesLabelGenerator(int)} method.  
     * If, for some reason, you want a different generator for individual 
     * items, you can override this method.
     *
     * @param row  the row index (zero based).
     * @param column  the column index (zero based).
     *
     * @return the generator (possibly <code>null</code>).
     */
    public CategoryLabelGenerator getLabelGenerator(int row, int column) {
        return getSeriesLabelGenerator(row);
    }

    /**
     * Returns the label generator for a series.
     *
     * @param series  the series index (zero based).
     *
     * @return the generator (possibly <code>null</code>).
     */
    public CategoryLabelGenerator getSeriesLabelGenerator(int series) {

        // return the generator for ALL series, if there is one...
        if (this.labelGenerator != null) {
            return this.labelGenerator;
        }

        // otherwise look up the generator table
        CategoryLabelGenerator generator
            = (CategoryLabelGenerator) this.labelGeneratorList.get(series);
        if (generator == null) {
            generator = this.baseLabelGenerator;
        }
        return generator;

    }

    /**
     * Sets the label generator for ALL series and sends a 
     * {@link RendererChangeEvent} to all registered listeners.
     *
     * @param generator  the generator (<code>null</code> permitted).
     */
    public void setLabelGenerator(CategoryLabelGenerator generator) {
        this.labelGenerator = generator;
        notifyListeners(new RendererChangeEvent(this));
    }

    /**
     * Sets the label generator for a series and sends a 
     * {@link RendererChangeEvent} to all registered listeners.
     *
     * @param series  the series index (zero based).
     * @param generator  the generator (<code>null</code> permitted).
     */
    public void setSeriesLabelGenerator(int series, 
                                        CategoryLabelGenerator generator) {
        this.labelGeneratorList.set(series, generator);
        notifyListeners(new RendererChangeEvent(this));
    }

    /**
     * Returns the base label generator.
     *
     * @return The generator (possibly <code>null</code>).
     */
    public CategoryLabelGenerator getBaseLabelGenerator() {
        return this.baseLabelGenerator;
    }

    /**
     * Sets the base label generator and sends a {@link RendererChangeEvent}
     * to all registered listeners.
     *
     * @param generator  the generator (<code>null</code> permitted).
     */
    public void setBaseLabelGenerator(CategoryLabelGenerator generator) {
        this.baseLabelGenerator = generator;
        notifyListeners(new RendererChangeEvent(this));
    }

    // TOOL TIP GENERATOR

    /**
     * Returns the tool tip generator that should be used for the specified 
     * item.  This method looks up the generator using the "three-layer" 
     * approach outlined in the general description of this interface.  You 
     * can override this method if you want to return a different generator per
     * item.
     *
     * @param row  the row index (zero-based).
     * @param column  the column index (zero-based).
     *
     * @return The generator (possibly <code>null</code>).
     */
    public CategoryToolTipGenerator getToolTipGenerator(int row, int column) {

        CategoryToolTipGenerator result = null;
        if (this.toolTipGenerator != null) {
            result = this.toolTipGenerator;
        }
        else {
            result = getSeriesToolTipGenerator(row);  
            if (result == null) {
                result = this.baseToolTipGenerator;   
            }
        }
        return result;
    }

    /**
     * Returns the tool tip generator that will be used for ALL items in the 
     * dataset (the "layer 0" generator).
     * 
     * @return A tool tip generator (possibly <code>null</code>).
     */
    public CategoryToolTipGenerator getToolTipGenerator() {
        return this.toolTipGenerator;    
    }
    
    /**
     * Sets the tool tip generator for ALL series and sends a 
     * {@link org.jfree.chart.event.RendererChangeEvent} to all registered 
     * listeners.
     * 
     * @param generator  the generator (<code>null</code> permitted).
     */
    public void setToolTipGenerator(CategoryToolTipGenerator generator) {
        this.toolTipGenerator = generator;
        notifyListeners(new RendererChangeEvent(this));
    }

    /**
     * Returns the tool tip generator for the specified series (a "layer 1" 
     * generator).
     *
     * @param series  the series index (zero-based).
     *
     * @return The tool tip generator (possibly <code>null</code>).
     */
    public CategoryToolTipGenerator getSeriesToolTipGenerator(int series) {
        return (CategoryToolTipGenerator) this.toolTipGeneratorList.get(series);
    }

    /**
     * Sets the tool tip generator for a series and sends a 
     * {@link org.jfree.chart.event.RendererChangeEvent} to all registered 
     * listeners.
     *
     * @param series  the series index (zero-based).
     * @param generator  the generator (<code>null</code> permitted).
     */
    public void setSeriesToolTipGenerator(int series, 
                                          CategoryToolTipGenerator generator) {
        this.toolTipGeneratorList.set(series, generator);
        notifyListeners(new RendererChangeEvent(this));
    }

    /**
     * Returns the base tool tip generator (the "layer 2" generator).
     *
     * @return The tool tip generator (possibly <code>null</code>).
     */
    public CategoryToolTipGenerator getBaseToolTipGenerator() {
        return this.baseToolTipGenerator;
    }

    /**
     * Sets the base tool tip generator and sends a 
     * {@link org.jfree.chart.event.RendererChangeEvent} to all registered 
     * listeners.
     *
     * @param generator  the generator (<code>null</code> permitted).
     */
    public void setBaseToolTipGenerator(CategoryToolTipGenerator generator) {
        this.baseToolTipGenerator = generator;
        notifyListeners(new RendererChangeEvent(this));
    }

    // URL GENERATOR
    
    /**
     * Returns the URL generator for a data item.  This method just calls the
     * getSeriesItemURLGenerator method, but you can override this behaviour if
     * you want to.
     *
     * @param row  the row index (zero based).
     * @param column  the column index (zero based).
     *
     * @return The URL generator.
     */
    public CategoryURLGenerator getItemURLGenerator(int row, int column) {
        return getSeriesItemURLGenerator(row);
    }

    /**
     * Returns the URL generator for a series.
     *
     * @param series  the series index (zero based).
     *
     * @return The URL generator for the series.
     */
    public CategoryURLGenerator getSeriesItemURLGenerator(int series) {

        // return the generator for ALL series, if there is one...
        if (this.itemURLGenerator != null) {
            return this.itemURLGenerator;
        }

        // otherwise look up the generator table
        CategoryURLGenerator generator
            = (CategoryURLGenerator) this.itemURLGeneratorList.get(series);
        if (generator == null) {
            generator = this.baseItemURLGenerator;
        }
        return generator;

    }

    /**
     * Sets the item URL generator for ALL series.
     *
     * @param generator  the generator.
     */
    public void setItemURLGenerator(CategoryURLGenerator generator) {
        this.itemURLGenerator = generator;
    }

    /**
     * Sets the URL generator for a series.
     *
     * @param series  the series index (zero based).
     * @param generator  the generator.
     */
    public void setSeriesItemURLGenerator(int series, 
                                          CategoryURLGenerator generator) {
        this.itemURLGeneratorList.set(series, generator);
    }

    /**
     * Returns the base item URL generator.
     *
     * @return The item URL generator.
     */
    public CategoryURLGenerator getBaseItemURLGenerator() {
        return this.baseItemURLGenerator;
    }

    /**
     * Sets the base item URL generator.
     *
     * @param generator  the item URL generator.
     */
    public void setBaseItemURLGenerator(CategoryURLGenerator generator) {
        this.baseItemURLGenerator = generator;
    }

    /**
     * Returns the number of rows in the dataset.  This value is updated in the
     * {@link AbstractCategoryItemRenderer#initialise} method.
     *
     * @return the row count.
     */
    public int getRowCount() {
        return this.rowCount;
    }

    /**
     * Returns the number of columns in the dataset.  This value is updated in 
     * the {@link AbstractCategoryItemRenderer#initialise} method.
     *
     * @return the column count.
     */
    public int getColumnCount() {
        return this.columnCount;
    }

    /**
     * Initialises the renderer and returns a state object that will be used 
     * for the remainder of the drawing process for a single chart.  The state 
     * object allows for the fact that the renderer may be used simultaneously 
     * by multiple threads (each thread will work with a separate state object).
     * <P>
     * Stores a reference to the {@link PlotRenderingInfo} object (which might 
     * be <code>null</code>), and then sets the useCategoriesPaint flag 
     * according to the special case conditions a) there is only one series 
     * and b) the categoriesPaint array is not null.
     *
     * @param g2  the graphics device.
     * @param dataArea  the data area.
     * @param plot  the plot.
     * @param rendererIndex  the renderer index.
     * @param info  an object for returning information about the structure of 
     *              the plot (<code>null</code> permitted).
     * 
     * @return the renderer state.
     *
     */
    public CategoryItemRendererState initialise(Graphics2D g2, 
                                                Rectangle2D dataArea,
                                                CategoryPlot plot, 
                                                int rendererIndex,
                                                PlotRenderingInfo info) {

        setPlot(plot);
        CategoryDataset data = plot.getDataset(rendererIndex);
        if (data != null) {
            this.rowCount = data.getRowCount();
            this.columnCount = data.getColumnCount();
        }
        else {
            this.rowCount = 0;
            this.columnCount = 0;
        }
        return new CategoryItemRendererState(info);

    }

    /**
     * Returns the range of values the renderer requires to display all the 
     * items from the specified dataset.
     * 
     * @param dataset  the dataset (<code>null</code> permitted).
     * 
     * @return The range (or <code>null</code> if the dataset is 
     *         <code>null</code> or empty).
     */
    public Range findRangeBounds(CategoryDataset dataset) {
        return DatasetUtilities.findRangeBounds(dataset);   
    }

    /**
     * Draws a background for the data area.  The default implementation just 
     * gets the plot to draw the outline, but some renderers will override this
     * behaviour.
     *
     * @param g2  the graphics device.
     * @param plot  the plot.
     * @param dataArea  the data area.
     */
    public void drawBackground(Graphics2D g2,
                               CategoryPlot plot,
                               Rectangle2D dataArea) {

        plot.drawBackground(g2, dataArea);

    }

    /**
     * Draws an outline for the data area.  The default implementation just 
     * gets the plot to draw the outline, but some renderers will override this
     * behaviour.
     *
     * @param g2  the graphics device.
     * @param plot  the plot.
     * @param dataArea  the data area.
     */
    public void drawOutline(Graphics2D g2,
                            CategoryPlot plot,
                            Rectangle2D dataArea) {

        plot.drawOutline(g2, dataArea);

    }

    /**
     * Draws a grid line against the domain axis.
     * <P>
     * Note that this default implementation assumes that the horizontal axis 
     * is the domain axis. If this is not the case, you will need to override 
     * this method.
     *
     * @param g2  the graphics device.
     * @param plot  the plot.
     * @param dataArea  the area for plotting data (not yet adjusted for any 
     *                  3D effect).
     * @param value  the Java2D value at which the grid line should be drawn.
     */
    public void drawDomainGridline(Graphics2D g2,
                                   CategoryPlot plot,
                                   Rectangle2D dataArea,
                                   double value) {

        Line2D line = null;
        PlotOrientation orientation = plot.getOrientation();

        if (orientation == PlotOrientation.HORIZONTAL) {
            line = new Line2D.Double(
                dataArea.getMinX(), value, dataArea.getMaxX(), value
            );
        }
        else if (orientation == PlotOrientation.VERTICAL) {
            line = new Line2D.Double(
                value, dataArea.getMinY(), value, dataArea.getMaxY()
            );
        }

        Paint paint = plot.getDomainGridlinePaint();
        if (paint == null) {
            paint = CategoryPlot.DEFAULT_GRIDLINE_PAINT;
        }
        g2.setPaint(paint);

        Stroke stroke = plot.getDomainGridlineStroke();
        if (stroke == null) {
            stroke = CategoryPlot.DEFAULT_GRIDLINE_STROKE;
        }
        g2.setStroke(stroke);

        g2.draw(line);

    }

    /**
     * Draws a grid line against the range axis.
     *
     * @param g2  the graphics device.
     * @param plot  the plot.
     * @param axis  the value axis.
     * @param dataArea  the area for plotting data (not yet adjusted for any 
     *                  3D effect).
     * @param value  the value at which the grid line should be drawn.
     *
     */
    public void drawRangeGridline(Graphics2D g2,
                                  CategoryPlot plot,
                                  ValueAxis axis,
                                  Rectangle2D dataArea,
                                  double value) {

        Range range = axis.getRange();
        if (!range.contains(value)) {
            return;
        }

        PlotOrientation orientation = plot.getOrientation();
        double v = axis.valueToJava2D(value, dataArea, plot.getRangeAxisEdge());
        Line2D line = null;
        if (orientation == PlotOrientation.HORIZONTAL) {
            line = new Line2D.Double(
                v, dataArea.getMinY(), v, dataArea.getMaxY()
            );
        }
        else if (orientation == PlotOrientation.VERTICAL) {
            line = new Line2D.Double(
                dataArea.getMinX(), v, dataArea.getMaxX(), v
            );
        }

        Paint paint = plot.getRangeGridlinePaint();
        if (paint == null) {
            paint = CategoryPlot.DEFAULT_GRIDLINE_PAINT;
        }
        g2.setPaint(paint);

        Stroke stroke = plot.getRangeGridlineStroke();
        if (stroke == null) {
            stroke = CategoryPlot.DEFAULT_GRIDLINE_STROKE;
        }
        g2.setStroke(stroke);

        g2.draw(line);

    }

    /**
     * Draws a marker for the range axis.
     *
     * @param g2  the graphics device (not <code>null</code>).
     * @param plot  the plot (not <code>null</code>).
     * @param axis  the range axis (not <code>null</code>).
     * @param marker  the marker to be drawn (not <code>null</code>).
     * @param dataArea  the area inside the axes (not <code>null</code>).
     */
    public void drawRangeMarker(Graphics2D g2,
                                CategoryPlot plot,
                                ValueAxis axis,
                                Marker marker,
                                Rectangle2D dataArea) {

        if (marker instanceof ValueMarker) {
            ValueMarker vm = (ValueMarker) marker;
            double value = vm.getValue();
            Range range = axis.getRange();

            if (!range.contains(value)) {
                return;
            }

            PlotOrientation orientation = plot.getOrientation();
            double v = axis.valueToJava2D(
                value, dataArea, plot.getRangeAxisEdge()
            );
            Line2D line = null;
            if (orientation == PlotOrientation.HORIZONTAL) {
                line = new Line2D.Double(
                    v, dataArea.getMinY(), v, dataArea.getMaxY()
                );
            }
            else if (orientation == PlotOrientation.VERTICAL) {
                line = new Line2D.Double(
                    dataArea.getMinX(), v, dataArea.getMaxX(), v
                );
            }

            g2.setPaint(marker.getPaint());
            g2.setStroke(marker.getStroke());
            g2.draw(line);
        
            String label = marker.getLabel();
            RectangleAnchor anchor = marker.getLabelAnchor();
            if (label != null) {
                Font labelFont = marker.getLabelFont();
                g2.setFont(labelFont);
                g2.setPaint(marker.getLabelPaint());
                Point2D coordinates = calculateRangeMarkerTextAnchorPoint(
                    g2, orientation, dataArea, line.getBounds2D(), 
                    marker.getLabelOffset(), 
                    marker.getLabelOffsetTypeForDomain(), 
                    marker.getLabelOffsetTypeForRange(), anchor
                );
                TextUtilities.drawAlignedString(
                    label, g2, 
                    (float) coordinates.getX(), (float) coordinates.getY(), 
                    marker.getLabelTextAnchor()
                );
            }
        }
        else if (marker instanceof IntervalMarker) {
            
            IntervalMarker im = (IntervalMarker) marker;
            double start = im.getStartValue();
            double end = im.getEndValue();
            Range range = axis.getRange();
            if (!(range.intersects(start, end))) {
                return;
            }
            
            // don't draw beyond the axis range...
            start = range.constrain(start);
            end = range.constrain(end);
            
            double v0 = axis.valueToJava2D(
                start, dataArea, plot.getRangeAxisEdge()
            );
            double v1 = axis.valueToJava2D(
                end, dataArea, plot.getRangeAxisEdge()
            );
            
            PlotOrientation orientation = plot.getOrientation();
            Rectangle2D rect = null;
            if (orientation == PlotOrientation.HORIZONTAL) {
                rect = new Rectangle2D.Double(
                    v0, dataArea.getMinY(), v1 - v0, dataArea.getHeight()
                );            
            }
            else if (orientation == PlotOrientation.VERTICAL) {
                rect = new Rectangle2D.Double(
                    dataArea.getMinX(), Math.min(v0, v1), 
                    dataArea.getWidth(), Math.abs(v1 - v0)
                );
            }
            Paint p = marker.getPaint();
            if (p instanceof GradientPaint) {
                GradientPaint gp = (GradientPaint) p;
                GradientPaintTransformer t = im.getGradientPaintTransformer();
                if (t != null) {
                    gp = t.transform(gp, rect);  
                }
                g2.setPaint(gp);
            }
            else {
                g2.setPaint(p);
            }
            g2.fill(rect);

            String label = marker.getLabel();
            RectangleAnchor anchor = marker.getLabelAnchor();
            if (label != null) {
                Font labelFont = marker.getLabelFont();
                g2.setFont(labelFont);
                g2.setPaint(marker.getLabelPaint());
                Point2D coordinates = calculateRangeMarkerTextAnchorPoint(
                    g2, orientation, dataArea, 
                    rect, marker.getLabelOffset(), 
                    marker.getLabelOffsetTypeForDomain(), 
                    marker.getLabelOffsetTypeForRange(), anchor
                );
                TextUtilities.drawAlignedString(
                    label, g2, 
                    (float) coordinates.getX(), (float) coordinates.getY(), 
                    marker.getLabelTextAnchor()
                );
            }
            
        }

    }

    /**
     * Calculates the (x, y) coordinates for drawing a marker label.
     * 
     * @param g2  the graphics device.
     * @param orientation  the plot orientation.
     * @param dataArea  the data area.
     * @param markerArea  the rectangle surrounding the marker.
     * @param markerOffset  the marker offset.
     * @param anchor  the label anchor.
     * 
     * @return The coordinates for drawing the marker label.
     */
    private Point2D calculateRangeMarkerTextAnchorPoint(Graphics2D g2, 
                                      PlotOrientation orientation,
                                      Rectangle2D dataArea,
                                      Rectangle2D markerArea,
                                      RectangleInsets markerOffset,
                                      LengthAdjustmentType labelOffsetForDomain,
                                      LengthAdjustmentType labelOffsetForRange,
                                      RectangleAnchor anchor) {
                                                     
        Rectangle2D anchorRect = null;
        if (orientation == PlotOrientation.HORIZONTAL) {
            anchorRect = markerOffset.createAdjustedRectangle(
                markerArea, labelOffsetForRange, labelOffsetForDomain
            );
        }
        else if (orientation == PlotOrientation.VERTICAL) {
            anchorRect = markerOffset.createAdjustedRectangle(
                markerArea, labelOffsetForDomain, labelOffsetForRange
            );
        }
        return RectangleAnchor.coordinates(anchorRect, anchor);
        
    }
    
    /**
     * Returns a legend item for a series.
     *
     * @param datasetIndex  the dataset index (zero-based).
     * @param series  the series index (zero-based).
     *
     * @return The legend item.
     */
    public LegendItem getLegendItem(int datasetIndex, int series) {

        CategoryPlot cp = getPlot();
        if (cp == null) {
            return null;
        }

        CategoryDataset dataset;
        dataset = cp.getDataset(datasetIndex);
        String label = dataset.getRowKey(series).toString();
        String description = label;
        Shape shape = getSeriesShape(series);
        Paint paint = getSeriesPaint(series);
        Paint outlinePaint = getSeriesOutlinePaint(series);
        Stroke outlineStroke = getSeriesOutlineStroke(series);

        return new LegendItem(
            label, description, shape, paint, outlineStroke, outlinePaint
        );

    }

    /**
     * Tests this renderer for equality with another object.
     *
     * @param obj  the object.
     *
     * @return <code>true</code> or <code>false</code>.
     */
    public boolean equals(Object obj) {

        if (obj == this) {
            return true;
        }
        if (!(obj instanceof AbstractCategoryItemRenderer)) {
            return false;
        }
        if (!super.equals(obj)) {
            return false;
        }

        AbstractCategoryItemRenderer that = (AbstractCategoryItemRenderer) obj;

        if (!ObjectUtilities.equal(this.labelGenerator, that.labelGenerator)) {
            return false;
        }
        if (!ObjectUtilities.equal(
            this.labelGeneratorList, that.labelGeneratorList
        )) {
            return false;
        }
        if (!ObjectUtilities.equal(
            this.baseLabelGenerator, that.baseLabelGenerator
        )) {
            return false;
        }
        if (!ObjectUtilities.equal(
            this.toolTipGenerator, that.toolTipGenerator
        )) {
            return false;
        }
        if (!ObjectUtilities.equal(
            this.toolTipGeneratorList, that.toolTipGeneratorList
        )) {
            return false;
        }
        if (!ObjectUtilities.equal(
            this.baseToolTipGenerator, that.baseToolTipGenerator
         )) {
            return false;
        }
        if (!ObjectUtilities.equal(
            this.itemURLGenerator, that.itemURLGenerator
        )) {
            return false;
        }
        if (!ObjectUtilities.equal(
            this.itemURLGeneratorList, that.itemURLGeneratorList
        )) {
            return false;
        }
        if (!ObjectUtilities.equal(
            this.baseItemURLGenerator, that.baseItemURLGenerator
        )) {
            return false;
        }

        return true;

    }
    
    /**
     * Returns a hash code for the renderer.
     * 
     * @return The hash code.
     */
    public int hashCode() {
        int result = super.hashCode();
        return result;
    }

    /**
     * Returns the drawing supplier from the plot.
     *
     * @return The drawing supplier (possibly <code>null</code>).
     */
    public DrawingSupplier getDrawingSupplier() {
        DrawingSupplier result = null;
        CategoryPlot cp = getPlot();
        if (cp != null) {
            result = cp.getDrawingSupplier();
        }
        return result;
    }

    /**
     * Draws an item label.
     *
     * @param g2  the graphics device.
     * @param orientation  the orientation.
     * @param dataset  the dataset.
     * @param row  the row.
     * @param column  the column.
     * @param x  the x coordinate (in Java2D space).
     * @param y  the y coordinate (in Java2D space).
     * @param negative  indicates a negative value (which affects the item 
     *                  label position).
     */
    protected void drawItemLabel(Graphics2D g2, 
                                 PlotOrientation orientation,
                                 CategoryDataset dataset, 
                                 int row, int column,
                                 double x, double y, 
                                 boolean negative) {
                                     
        CategoryLabelGenerator generator = getLabelGenerator(row, column);
        if (generator != null) {
            Font labelFont = getItemLabelFont(row, column);
            Paint paint = getItemLabelPaint(row, column);
            g2.setFont(labelFont);
            g2.setPaint(paint);
            String label = generator.generateLabel(dataset, row, column);
            ItemLabelPosition position = null;
            if (!negative) {
                position = getPositiveItemLabelPosition(row, column);
            }
            else {
                position = getNegativeItemLabelPosition(row, column);
            }
            Point2D anchorPoint = calculateLabelAnchorPoint(
                position.getItemLabelAnchor(), x, y, orientation
            );
            TextUtilities.drawRotatedString(
                label, g2, 
                (float) anchorPoint.getX(), (float) anchorPoint.getY(),
                position.getTextAnchor(), 
                position.getAngle(), position.getRotationAnchor()
            );
        }

    }
    
    /**
     * Returns an independent copy of the renderer.  The <code>plot</code> 
     * reference is shallow copied.
     * 
     * @return A clone.
     * 
     * @throws CloneNotSupportedException  can be thrown if one of the objects 
     *         belonging to the renderer does not support cloning (for example,
     *         an item label generator).
     */
    public Object clone() throws CloneNotSupportedException {
        
        AbstractCategoryItemRenderer clone 
            = (AbstractCategoryItemRenderer) super.clone();

        if (this.labelGenerator != null) {
            if (this.labelGenerator instanceof PublicCloneable) {
                PublicCloneable pc = (PublicCloneable) this.labelGenerator;
                clone.labelGenerator = (CategoryLabelGenerator) pc.clone();
            }
            else {
                throw new CloneNotSupportedException(
                    "ItemLabelGenerator not cloneable."
                );
            }
        }

        if (this.labelGeneratorList != null) {
            clone.labelGeneratorList 
                = (ObjectList) this.labelGeneratorList.clone();
        }
        
        if (this.baseLabelGenerator != null) {
            if (this.baseLabelGenerator instanceof PublicCloneable) {
                PublicCloneable pc = (PublicCloneable) this.baseLabelGenerator;
                clone.baseLabelGenerator = (CategoryLabelGenerator) pc.clone();
            }
            else {
                throw new CloneNotSupportedException(
                    "ItemLabelGenerator not cloneable."
                );
            }
        }
        
        if (this.toolTipGenerator != null) {
            if (this.toolTipGenerator instanceof PublicCloneable) {
                PublicCloneable pc = (PublicCloneable) this.toolTipGenerator;
                clone.toolTipGenerator = (CategoryToolTipGenerator) pc.clone();
            }
            else {
                throw new CloneNotSupportedException(
                    "Tool tip generator not cloneable."
                );
            }
        }

        if (this.toolTipGeneratorList != null) {
            clone.toolTipGeneratorList 
                = (ObjectList) this.toolTipGeneratorList.clone();
        }
        
        if (this.baseToolTipGenerator != null) {
            if (this.baseToolTipGenerator instanceof PublicCloneable) {
                PublicCloneable pc 
                    = (PublicCloneable) this.baseToolTipGenerator;
                clone.baseToolTipGenerator 
                    = (CategoryToolTipGenerator) pc.clone();
            }
            else {
                throw new CloneNotSupportedException(
                    "Base tool tip generator not cloneable."
                );
            }
        }
        
        if (this.itemURLGenerator != null) {
            if (this.itemURLGenerator instanceof PublicCloneable) {
                PublicCloneable pc = (PublicCloneable) this.itemURLGenerator;
                clone.itemURLGenerator = (CategoryURLGenerator) pc.clone();
            }
            else {
                throw new CloneNotSupportedException(
                    "Item URL generator not cloneable."
                );
            }
        }

        if (this.itemURLGeneratorList != null) {
            clone.itemURLGeneratorList 
                = (ObjectList) this.itemURLGeneratorList.clone();
        }

        if (this.baseItemURLGenerator != null) {
            if (this.baseItemURLGenerator instanceof PublicCloneable) {
                PublicCloneable pc = (PublicCloneable) this.baseItemURLGenerator;   
                clone.baseItemURLGenerator = (CategoryURLGenerator) pc.clone();
            }
            else {
                throw new CloneNotSupportedException(
                    "Base item URL generator not cloneable."
                );   
            }
        }
        
        return clone;
    }

    /**
     * Returns a domain axis for a plot.
     * 
     * @param plot  the plot.
     * @param index  the axis index.
     * 
     * @return A domain axis.
     */
    protected CategoryAxis getDomainAxis(CategoryPlot plot, int index) {
        CategoryAxis result = plot.getDomainAxis(index);
        if (result == null) {
            result = plot.getDomainAxis();
        }
        return result;
    }

    /**
     * Returns a range axis for a plot.
     * 
     * @param plot  the plot.
     * @param index  the axis index (<code>null</code> for the primary axis).
     * 
     * @return A range axis.
     */
    protected ValueAxis getRangeAxis(CategoryPlot plot, int index) {
        ValueAxis result = plot.getRangeAxis(index);
        if (result == null) {
            result = plot.getRangeAxis();
        }
        return result;
    }
    
    /**
     * Returns a (possibly empty) collection of legend items for the series
     * that this renderer is responsible for drawing.
     *
     * @return The legend item collection (never <code>null</code>).
     */
    public LegendItemCollection getLegendItems() {
        if (this.plot == null) {
            return new LegendItemCollection();
        }
        LegendItemCollection result = new LegendItemCollection();
        int index = this.plot.getIndexOf(this);
        CategoryDataset dataset = this.plot.getDataset(index);
        if (dataset != null) {
            int seriesCount = dataset.getRowCount();
            for (int i = 0; i < seriesCount; i++) {
                LegendItem item = getLegendItem(index, i);
                if (item != null) {
                    result.add(item);
                }
            }
   
        }
        return result;
    }

}