/**
     * Returns the maximum label width as a percentage of the plot width.
     * 
     * @return The width (a percentage, where 0.20 = 20 percent).
     */
    public double getMaximumLabelWidth() {
        return this.maximumLabelWidth;   
    }
    
    /**
     * Sets the maximum label width as a percentage of the plot width and sends
     * a {@link PlotChangeEvent} to all registered listeners.
     * 
     * @param width  the width (a percentage, where 0.20 = 20 percent).
     */
    public void setMaximumLabelWidth(double width) {
        this.maximumLabelWidth = width;
        notifyListeners(new PlotChangeEvent(this));
    }
    
    /**
     * Returns the flag that controls whether or not label linking lines are
     * visible.
     * 
     * @return A boolean.
     */
    public boolean getLabelLinksVisible() {
        return this.labelLinksVisible;
    }
    
    /**
     * Sets the flag that controls whether or not label linking lines are 
     * visible and sends a {@link PlotChangeEvent} to all registered listeners.
     * Please take care when hiding the linking lines - depending on the data 
     * values, the labels can be displayed some distance away from the
     * corresponding pie section.
     * 
     * @param visible  the flag.
     */
    public void setLabelLinksVisible(boolean visible) {
        this.labelLinksVisible = visible;
        notifyListeners(new PlotChangeEvent(this));
    }
    
    /**
     * Returns the margin (expressed as a percentage of the width or height) 
     * between the edge of the pie and the link point.
     * 
     * @return The link margin (as a percentage, where 0.05 is five percent).
     */
    public double getLabelLinkMargin() {
        return this.labelLinkMargin;   
    }
    
    /**
     * Sets the link margin and sends a {@link PlotChangeEvent} to all 
     * registered listeners.
     * 
     * @param margin  the margin.
     */
    public void setLabelLinkMargin(double margin) {
        this.labelLinkMargin = margin;
        notifyListeners(new PlotChangeEvent(this));
    }
    
    /**
     * Returns the paint used for the lines that connect pie sections to their 
     * corresponding labels.
     * 
     * @return The paint (never <code>null</code>).
     */
    public Paint getLabelLinkPaint() {
        return this.labelLinkPaint;   
    }
    
    /**
     * Sets the paint used for the lines that connect pie sections to their 
     * corresponding labels, and sends a {@link PlotChangeEvent} to all 
     * registered listeners.
     * 
     * @param paint  the paint (<code>null</code> not permitted).
     */
    public void setLabelLinkPaint(Paint paint) {
        if (paint == null) {
            throw new IllegalArgumentException("Null 'paint' argument.");
        }
        this.labelLinkPaint = paint;
        notifyListeners(new PlotChangeEvent(this));
    }
    
    /**
     * Returns the stroke used for the label linking lines.
     * 
     * @return The stroke.
     */
    public Stroke getLabelLinkStroke() {
        return this.labelLinkStroke;   
    }
    
    /**
     * Sets the link stroke and sends a {@link PlotChangeEvent} to all 
     * registered listeners.
     * 
     * @param stroke  the stroke.
     */
    public void setLabelLinkStroke(Stroke stroke) {
        if (stroke == null) {
            throw new IllegalArgumentException("Null 'stroke' argument.");
        }
        this.labelLinkStroke = stroke;
        notifyListeners(new PlotChangeEvent(this));
    }
    
    /**
     * Returns the section label font.
     *
     * @return The font (never <code>null</code>).
     */
    public Font getLabelFont() {
        return this.labelFont;
    }

    /**
     * Sets the section label font and sends a {@link PlotChangeEvent} to all 
     * registered listeners.
     *
     * @param font  the font (<code>null</code> not permitted).
     */
    public void setLabelFont(Font font) {
        if (font == null) {
            throw new IllegalArgumentException("Null 'font' argument.");
        }
        this.labelFont = font;
        notifyListeners(new PlotChangeEvent(this));
    }

    /**
     * Returns the section label paint.
     *
     * @return The paint (never <code>null</code>).
     */
    public Paint getLabelPaint() {
        return this.labelPaint;
    }

    /**
     * Sets the section label paint and sends a {@link PlotChangeEvent} to all 
     * registered listeners.
     *
     * @param paint  the paint (<code>null</code> not permitted).
     */
    public void setLabelPaint(Paint paint) {
        if (paint == null) {
            throw new IllegalArgumentException("Null 'paint' argument.");
        }
        this.labelPaint = paint;
        notifyListeners(new PlotChangeEvent(this));
    }

    /**
     * Returns the section label background paint.
     *
     * @return The paint (possibly <code>null</code>).
     */
    public Paint getLabelBackgroundPaint() {
        return this.labelBackgroundPaint;
    }

    /**
     * Sets the section label background paint and sends a 
     * {@link PlotChangeEvent} to all registered listeners.
     *
     * @param paint  the paint (<code>null</code> permitted).
     */
    public void setLabelBackgroundPaint(Paint paint) {
        this.labelBackgroundPaint = paint;
        notifyListeners(new PlotChangeEvent(this));
    }

    /**
     * Returns the section label outline paint.
     *
     * @return The paint (possibly <code>null</code>).
     */
    public Paint getLabelOutlinePaint() {
        return this.labelOutlinePaint;
    }

    /**
     * Sets the section label outline paint and sends a 
     * {@link PlotChangeEvent} to all registered listeners.
     *
     * @param paint  the paint (<code>null</code> permitted).
     */
    public void setLabelOutlinePaint(Paint paint) {
        this.labelOutlinePaint = paint;
        notifyListeners(new PlotChangeEvent(this));
    }

    /**
     * Returns the section label outline stroke.
     *
     * @return The stroke (possibly <code>null</code>).
     */
    public Stroke getLabelOutlineStroke() {
        return this.labelOutlineStroke;
    }

    /**
     * Sets the section label outline stroke and sends a 
     * {@link PlotChangeEvent} to all registered listeners.
     *
     * @param stroke  the stroke (<code>null</code> permitted).
     */
    public void setLabelOutlineStroke(Stroke stroke) {
        this.labelOutlineStroke = stroke;
        notifyListeners(new PlotChangeEvent(this));
    }

    /**
     * Returns the section label shadow paint.
     *
     * @return The paint (possibly <code>null</code>).
     */
    public Paint getLabelShadowPaint() {
        return this.labelShadowPaint;
    }

    /**
     * Sets the section label shadow paint and sends a {@link PlotChangeEvent}
     * to all registered listeners.
     *
     * @param paint  the paint (<code>null</code> permitted).
     */
    public void setLabelShadowPaint(Paint paint) {
        this.labelShadowPaint = paint;
        notifyListeners(new PlotChangeEvent(this));
    }

    /**
     * Returns the tool tip generator, an object that is responsible for 
     * generating the text items used for tool tips by the plot.  If the 
     * generator is <code>null</code>, no tool tips will be created.
     *
     * @return The generator (possibly <code>null</code>).
     */
    public PieToolTipGenerator getToolTipGenerator() {
        return this.toolTipGenerator;
    }

    /**
     * Sets the tool tip generator and sends a {@link PlotChangeEvent} to all 
     * registered listeners.  Set the generator to <code>null</code> if you 
     * don't want any tool tips.
     *
     * @param generator  the generator (<code>null</code> permitted).
     */
    public void setToolTipGenerator(PieToolTipGenerator generator) {
        this.toolTipGenerator = generator;
        notifyListeners(new PlotChangeEvent(this));
    }

    /**
     * Returns the URL generator.
     *
     * @return The generator (possibly <code>null</code>).
     */
    public PieURLGenerator getURLGenerator() {
        return this.urlGenerator;
    }

    /**
     * Sets the URL generator and sends a {@link PlotChangeEvent} to all 
     * registered listeners.
     *
     * @param generator  the generator (<code>null</code> permitted).
     */
    public void setURLGenerator(PieURLGenerator generator) {
        this.urlGenerator = generator;
        notifyListeners(new PlotChangeEvent(this));
    }

    /**
     * Returns the minimum arc angle that will be drawn.  Pie sections for an 
     * angle smaller than this are not drawn, to avoid a JDK bug.
     *
     * @return The minimum angle.
     */
    public double getMinimumArcAngleToDraw() {
        return this.minimumArcAngleToDraw;
    }

    /**
     * Sets the minimum arc angle that will be drawn.  Pie sections for an 
     * angle smaller than this are not drawn, to avoid a JDK bug.  See this 
     * link for details:
     * <br><br>
     * <a href="http://www.jfree.org/phpBB2/viewtopic.php?t=2707">
     * http://www.jfree.org/phpBB2/viewtopic.php?t=2707</a>
     * <br><br>
     * ...and this bug report in the Java Bug Parade:
     * <br><br>
     * <a href=
     * "http://developer.java.sun.com/developer/bugParade/bugs/4836495.html">
     * http://developer.java.sun.com/developer/bugParade/bugs/4836495.html</a>
     *
     * @param angle  the minimum angle.
     */
    public void setMinimumArcAngleToDraw(double angle) {
        this.minimumArcAngleToDraw = angle;
    }
    
    /**
     * Returns the shape used for legend items.
     * 
     * @return The shape.
     */
    public Shape getLegendItemShape() {
        return this.legendItemShape;
    }

    /**
     * Sets the shape used for legend items.
     * 
     * @param shape  the shape (<code>null</code> not permitted).
     */
    public void setLegendItemShape(Shape shape) {
        if (shape == null) {
            throw new IllegalArgumentException("Null 'shape' argument.");
        }
        this.legendItemShape = shape;
        notifyListeners(new PlotChangeEvent(this));
    }
    
    /**
     * Returns the legend label tool tip generator.
     * 
     * @return The legend label tool tip generator (possibly <code>null</code>).
     */
    public PieSectionLabelGenerator getLegendLabelToolTipGenerator() {
        return this.legendLabelToolTipGenerator;
    }
    
    /**
     * Sets the legend label tool tip generator and sends a 
     * {@link PlotChangeEvent} to all registered listeners.
     * 
     * @param generator  the generator (<code>null</code> permitted).
     */
    public void setLegendLabelToolTipGenerator(
            PieSectionLabelGenerator generator) {
        this.legendLabelToolTipGenerator = generator;
        notifyListeners(new PlotChangeEvent(this));
    }
    
    /**
     * Returns the legend label generator.
     * 
     * @return The legend label generator (never <code>null</code>).
     */
    public PieSectionLabelGenerator getLegendLabelGenerator() {
        return this.legendLabelGenerator;
    }
    
    /**
     * Sets the legend label generator and sends a {@link PlotChangeEvent} to 
     * all registered listeners.
     *