* Returns the range axis.
     *
     * @return The range axis.
     */
    public ValueAxis getRangeAxis() {
        return this.rangeAxis;
    }

    /**
     * Sets the range axis for the plot.
     *
     * @param axis  the new axis.
     */
    public void setRangeAxis(ValueAxis axis) {

        if (axis != null) {
            axis.setPlot(this);
            axis.addChangeListener(this);
        }

        // plot is likely registered as a listener with the existing axis...
        if (this.rangeAxis != null) {
            this.rangeAxis.removeChangeListener(this);
        }

        this.rangeAxis = axis;

    }

    /**
     * Returns the lower bound for the thermometer.  The data value can be set 
     * lower than this, but it will not be shown in the thermometer.
     *
     * @return The lower bound.
     *
     */
    public double getLowerBound() {
        return this.lowerBound;
    }

    /**
     * Sets the lower bound for the thermometer.
     *
     * @param lower the lower bound.
     */
    public void setLowerBound(double lower) {
        this.lowerBound = lower;
        setAxisRange();
    }

    /**
     * Returns the upper bound for the thermometer.  The data value can be set 
     * higher than this, but it will not be shown in the thermometer.
     *
     * @return The upper bound.
     */
    public double getUpperBound() {
        return this.upperBound;
    }

    /**
     * Sets the upper bound for the thermometer.
     *
     * @param upper the upper bound.
     */
    public void setUpperBound(double upper) {
        this.upperBound = upper;
        setAxisRange();
    }

    /**
     * Sets the lower and upper bounds for the thermometer.
     *
     * @param lower  the lower bound.
     * @param upper  the upper bound.
     */
    public void setRange(double lower, double upper) {
        this.lowerBound = lower;
        this.upperBound = upper;
        setAxisRange();
    }

    /**
     * Returns the padding for the thermometer.  This is the space inside the 
     * plot area.
     *
     * @return The padding.
     */
    public RectangleInsets getPadding() {
        return this.padding;
    }

    /**
     * Sets the padding for the thermometer.
     *
     * @param padding  the padding.
     */
    public void setPadding(RectangleInsets padding) {
        this.padding = padding;
        notifyListeners(new PlotChangeEvent(this));
    }

    /**
     * Returns the stroke used to draw the thermometer outline.
     *
     * @return The stroke.
     */
    public Stroke getThermometerStroke() {
        return this.thermometerStroke;
    }

    /**
     * Sets the stroke used to draw the thermometer outline.
     *
     * @param s  the new stroke (null ignored).
     */
    public void setThermometerStroke(Stroke s) {
        if (s != null) {
            this.thermometerStroke = s;
            notifyListeners(new PlotChangeEvent(this));
        }
    }

    /**
     * Returns the paint used to draw the thermometer outline.
     *
     * @return The paint.
     */
    public Paint getThermometerPaint() {
        return this.thermometerPaint;
    }

    /**
     * Sets the paint used to draw the thermometer outline.
     *
     * @param paint  the new paint (null ignored).
     */
    public void setThermometerPaint(Paint paint) {
        if (paint != null) {
            this.thermometerPaint = paint;
            notifyListeners(new PlotChangeEvent(this));
        }
    }

    /**
     * Returns the unit display type (none/Fahrenheit/Celcius/Kelvin).
     *
     * @return The units type.
     */
    public int getUnits() {
        return this.units;
    }

    /**
     * Sets the units to be displayed in the thermometer.
     * <p>
     * Use one of the following constants:
     *
     * <ul>
     * <li>UNITS_NONE : no units displayed.</li>
     * <li>UNITS_FAHRENHEIT : units displayed in Fahrenheit.</li>
     * <li>UNITS_CELCIUS : units displayed in Celcius.</li>
     * <li>UNITS_KELVIN : units displayed in Kelvin.</li>
     * </ul>
     *
     * @param u  the new unit type.
     */
    public void setUnits(int u) {
        if ((u >= 0) && (u < UNITS.length)) {
            if (this.units != u) {
                this.units = u;
                notifyListeners(new PlotChangeEvent(this));
            }
        }
    }

    /**
     * Sets the unit type.
     *
     * @param u  the unit type (null ignored).
     */
    public void setUnits(String u) {
        if (u == null) {
            return;
        }

        u = u.toUpperCase().trim();
        for (int i = 0; i < UNITS.length; ++i) {
            if (u.equals(UNITS[i].toUpperCase().trim())) {
                setUnits(i);
                i = UNITS.length;
            }
        }
    }

    /**
     * Returns the value location.
     *
     * @return The location.
     */
    public int getValueLocation() {
        return this.valueLocation;
    }

    /**
     * Sets the location at which the current value is displayed.
     * <P>
     * The location can be one of the constants:
     * <code>NONE</code>,
     * <code>RIGHT</code>
     * <code>LEFT</code> and
     * <code>BULB</code>.
     *
     * @param location  the location.
     */
    public void setValueLocation(int location) {
        if ((location >= 0) && (location < 4)) {
            this.valueLocation = location;
            notifyListeners(new PlotChangeEvent(this));
        }
        else {
            throw new IllegalArgumentException("Location not recognised.");
        }
    }

    /**
     * Sets the location at which the axis is displayed with reference to the
     * bulb.
     * <P>
     * The location can be one of the constants:
     *   <code>NONE</code>,
     *   <code>RIGHT</code> and
     *   <code>LEFT</code>.
     *
     * @param location  the location.
     */
    public void setAxisLocation(int location) {
        if ((location >= 0) && (location < 3)) {
            this.axisLocation = location;
            notifyListeners(new PlotChangeEvent(this));
        }
        else {
            throw new IllegalArgumentException("Location not recognised.");
        }
    }

    /**
     * Returns the axis location.
     *
     * @return The location.
     */
    public int getAxisLocation() {
        return this.axisLocation;
    }

    /**
     * Gets the font used to display the current value.
     *
     * @return The font.
     */
    public Font getValueFont() {
        return this.valueFont;
    }

    /**
     * Sets the font used to display the current value.
     *
     * @param f  the new font.
     */
    public void setValueFont(Font f) {
        if ((f != null) && (!this.valueFont.equals(f))) {
            this.valueFont = f;
            notifyListeners(new PlotChangeEvent(this));
        }
    }

    /**
     * Gets the paint used to display the current value.
    *
     * @return The paint.
     */
    public Paint getValuePaint() {
        return this.valuePaint;
    }

    /**
     * Sets the paint used to display the current value.
     *
     * @param p  the new paint.
     */
    public void setValuePaint(Paint p) {
        if ((p != null) && (!this.valuePaint.equals(p))) {
            this.valuePaint = p;
            notifyListeners(new PlotChangeEvent(this));
        }
    }

    /**
     * Sets the formatter for the value label.
     *
     * @param formatter  the new formatter.
     */
    public void setValueFormat(NumberFormat formatter) {
        if (formatter != null) {
            this.valueFormat = formatter;
            notifyListeners(new PlotChangeEvent(this));
        }
    }

    /**
     * Returns the default mercury paint.
     *
     * @return The paint.
     */
    public Paint getMercuryPaint() {
        return this.mercuryPaint;
    }

    /**
     * Sets the default mercury paint.
     *
     * @param paint  the new paint.
     */
    public void setMercuryPaint(Paint paint) {
        this.mercuryPaint = paint;
        notifyListeners(new PlotChangeEvent(this));
    }

    /**
     * Returns the flag that controls whether not value lines are displayed.
     *
     * @return The flag.
     */
    public boolean getShowValueLines() {
        return this.showValueLines;
    }

    /**
     * Sets the display as to whether to show value lines in the output.
     *
     * @param b Whether to show value lines in the thermometer
     */
    public void setShowValueLines(boolean b) {
        this.showValueLines = b;
        notifyListeners(new PlotChangeEvent(this));
    }

    /**
     * Sets information for a particular range.
     *
     * @param range  the range to specify information about.
     * @param low  the low value for the range
     * @param hi  the high value for the range
     */
    public void setSubrangeInfo(int range, double low, double hi) {
        setSubrangeInfo(range, low, hi, low, hi);
    }

    /**
     * Sets the subrangeInfo attribute of the ThermometerPlot object
     *
     * @param range  the new rangeInfo value.
     * @param rangeLow  the new rangeInfo value
     * @param rangeHigh  the new rangeInfo value
     * @param displayLow  the new rangeInfo value
     * @param displayHigh  the new rangeInfo value
     */
    public void setSubrangeInfo(int range,
                                double rangeLow, double rangeHigh,
                                double displayLow, double displayHigh) {

        if ((range >= 0) && (range < 3)) {
            setSubrange(range, rangeLow, rangeHigh);
            setDisplayRange(range, displayLow, displayHigh);
            setAxisRange();
            notifyListeners(new PlotChangeEvent(this));
        }