jfreechart example source code file (SymbolAxis.java)

This example jfreechart source code file (SymbolAxis.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - jfreechart tags/keywords

awt, axisstate, basicstroke, geometry, io, list, list, paint, paint, rectangle2d, rectangle2d, rectangleedge, string, string, symbolaxis, text, textanchor, util, valuetick

The jfreechart SymbolAxis.java source code

/* ===========================================================
 * JFreeChart : a free chart library for the Java(tm) platform
 * ===========================================================
 *
 * (C) Copyright 2000-2008, 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.]
 *
 * ---------------
 * SymbolAxis.java
 * ---------------
 * (C) Copyright 2002-2008, by Anthony Boulestreau and Contributors.
 *
 * Original Author:  Anthony Boulestreau;
 * Contributor(s):   David Gilbert (for Object Refinery Limited);
 *
 *
 * Changes
 * -------
 * 29-Mar-2002 : First version (AB);
 * 19-Apr-2002 : Updated formatting and import statements (DG);
 * 21-Jun-2002 : Make change to use the class TickUnit - remove valueToString()
 *               method and add SymbolicTickUnit (AB);
 * 25-Jun-2002 : Removed redundant code (DG);
 * 25-Jul-2002 : Changed order of parameters in ValueAxis constructor (DG);
 * 05-Sep-2002 : Updated constructor to reflect changes in the Axis class (DG);
 * 08-Nov-2002 : Moved to new package com.jrefinery.chart.axis (DG);
 * 14-Feb-2003 : Added back missing constructor code (DG);
 * 26-Mar-2003 : Implemented Serializable (DG);
 * 14-May-2003 : Renamed HorizontalSymbolicAxis --> SymbolicAxis and merged in
 *               VerticalSymbolicAxis (DG);
 * 12-Aug-2003 : Fixed bug where refreshTicks() method has different signature
 *               to super class (DG);
 * 29-Oct-2003 : Added workaround for font alignment in PDF output (DG);
 * 02-Nov-2003 : Added code to avoid overlapping labels (MR);
 * 07-Nov-2003 : Modified to use new tick classes (DG);
 * 18-Nov-2003 : Fixed bug where symbols are not being displayed on the
 *               axis (DG);
 * 24-Nov-2003 : Added fix for gridlines on zooming (bug id 834643) (DG);
 * 21-Jan-2004 : Update for renamed method in ValueAxis (DG);
 * 11-Mar-2004 : Modified the way the background grid color is being drawn, see
 *               this thread:
 *               http://www.jfree.org/phpBB2/viewtopic.php?p=22973 (DG);
 * 16-Mar-2004 : Added plotState to draw() method (DG);
 * 07-Apr-2004 : Modified string bounds calculation (DG);
 * 28-Mar-2005 : Renamed autoRangeIncludesZero() --> getAutoRangeIncludesZero()
 *               and autoRangeStickyZero() --> getAutoRangeStickyZero() (DG);
 * 05-Jul-2005 : Fixed signature on refreshTicks() method - see bug report
 *               1232264 (DG);
 * 06-Jul-2005 : Renamed SymbolicAxis --> SymbolAxis, added equals() method,
 *               renamed getSymbolicValue() --> getSymbols(), renamed
 *               symbolicGridPaint --> gridBandPaint, fixed serialization of
 *               gridBandPaint, renamed symbolicGridLinesVisible -->
 *               gridBandsVisible, eliminated symbolicGridLineList (DG);
 * ------------- JFREECHART 1.0.x ---------------------------------------------
 * 02-Feb-2007 : Removed author tags all over JFreeChart sources (DG);
 * 28-Feb-2007 : Fixed bug 1669302 (tick label overlap) (DG);
 * 25-Jul-2007 : Added new field for alternate grid band paint (DG);
 * 15-Aug-2008 : Use alternate grid band paint when drawing (DG);
 *
 */

package org.jfree.chart.axis;

import java.awt.BasicStroke;
import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics2D;
import java.awt.Paint;
import java.awt.Shape;
import java.awt.Stroke;
import java.awt.geom.Rectangle2D;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;
import java.text.NumberFormat;
import java.util.Arrays;
import java.util.Iterator;
import java.util.List;

import org.jfree.chart.event.AxisChangeEvent;
import org.jfree.chart.plot.Plot;
import org.jfree.chart.plot.PlotRenderingInfo;
import org.jfree.chart.plot.ValueAxisPlot;
import org.jfree.data.Range;
import org.jfree.io.SerialUtilities;
import org.jfree.text.TextUtilities;
import org.jfree.ui.RectangleEdge;
import org.jfree.ui.TextAnchor;
import org.jfree.util.PaintUtilities;

/**
 * A standard linear value axis that replaces integer values with symbols.
 */
public class SymbolAxis extends NumberAxis implements Serializable {

    /** For serialization. */
    private static final long serialVersionUID = 7216330468770619716L;

    /** The default grid band paint. */
    public static final Paint DEFAULT_GRID_BAND_PAINT
            = new Color(232, 234, 232, 128);

    /**
     * The default paint for alternate grid bands.
     *
     * @since 1.0.7
     */
    public static final Paint DEFAULT_GRID_BAND_ALTERNATE_PAINT
            = new Color(0, 0, 0, 0);  // transparent

    /** The list of symbols to display instead of the numeric values. */
    private List symbols;

    /** Flag that indicates whether or not grid bands are visible. */
    private boolean gridBandsVisible;

    /** The paint used to color the grid bands (if the bands are visible). */
    private transient Paint gridBandPaint;

    /**
     * The paint used to fill the alternate grid bands.
     *
     * @since 1.0.7
     */
    private transient Paint gridBandAlternatePaint;

    /**
     * Constructs a symbol axis, using default attribute values where
     * necessary.
     *
     * @param label  the axis label (<code>null permitted).
     * @param sv  the list of symbols to display instead of the numeric
     *            values.
     */
    public SymbolAxis(String label, String[] sv) {
        super(label);
        this.symbols = Arrays.asList(sv);
        this.gridBandsVisible = true;
        this.gridBandPaint = DEFAULT_GRID_BAND_PAINT;
        this.gridBandAlternatePaint = DEFAULT_GRID_BAND_ALTERNATE_PAINT;
        setAutoTickUnitSelection(false, false);
        setAutoRangeStickyZero(false);

    }

    /**
     * Returns an array of the symbols for the axis.
     *
     * @return The symbols.
     */
    public String[] getSymbols() {
        String[] result = new String[this.symbols.size()];
        result = (String[]) this.symbols.toArray(result);
        return result;
    }

    /**
     * Returns <code>true if the grid bands are showing, and
     * <code>false otherwise.
     *
     * @return <code>true if the grid bands are showing, and
     *         <code>false otherwise.
     *
     * @see #setGridBandsVisible(boolean)
     */
    public boolean isGridBandsVisible() {
        return this.gridBandsVisible;
    }

    /**
     * Sets the visibility of the grid bands and notifies registered
     * listeners that the axis has been modified.
     *
     * @param flag  the new setting.
     *
     * @see #isGridBandsVisible()
     */
    public void setGridBandsVisible(boolean flag) {
        if (this.gridBandsVisible != flag) {
            this.gridBandsVisible = flag;
            notifyListeners(new AxisChangeEvent(this));
        }
    }

    /**
     * Returns the paint used to color the grid bands.
     *
     * @return The grid band paint (never <code>null).
     *
     * @see #setGridBandPaint(Paint)
     * @see #isGridBandsVisible()
     */
    public Paint getGridBandPaint() {
        return this.gridBandPaint;
    }

    /**
     * Sets the grid band paint and sends an {@link AxisChangeEvent} to
     * all registered listeners.
     *
     * @param paint  the paint (<code>null not permitted).
     *
     * @see #getGridBandPaint()
     */
    public void setGridBandPaint(Paint paint) {
        if (paint == null) {
            throw new IllegalArgumentException("Null 'paint' argument.");
        }
        this.gridBandPaint = paint;
        notifyListeners(new AxisChangeEvent(this));
    }

    /**
     * Returns the paint used for alternate grid bands.
     *
     * @return The paint (never <code>null).
     *
     * @see #setGridBandAlternatePaint(Paint)
     * @see #getGridBandPaint()
     *
     * @since 1.0.7
     */
    public Paint getGridBandAlternatePaint() {
        return this.gridBandAlternatePaint;
    }

    /**
     * Sets the paint used for alternate grid bands and sends a
     * {@link AxisChangeEvent} to all registered listeners.
     *
     * @param paint  the paint (<code>null not permitted).
     *
     * @see #getGridBandAlternatePaint()
     * @see #setGridBandPaint(Paint)
     *
     * @since 1.0.7
     */
    public void setGridBandAlternatePaint(Paint paint) {
        if (paint == null) {
            throw new IllegalArgumentException("Null 'paint' argument.");
        }
        this.gridBandAlternatePaint = paint;
        notifyListeners(new AxisChangeEvent(this));
    }

    /**
     * This operation is not supported by this axis.
     *
     * @param g2  the graphics device.
     * @param dataArea  the area in which the plot and axes should be drawn.
     * @param edge  the edge along which the axis is drawn.
     */
    protected void selectAutoTickUnit(Graphics2D g2, Rectangle2D dataArea,
                                      RectangleEdge edge) {
        throw new UnsupportedOperationException();
    }

    /**
     * Draws the axis on a Java 2D graphics device (such as the screen or a
     * printer).
     *
     * @param g2  the graphics device (<code>null not permitted).
     * @param cursor  the cursor location.
     * @param plotArea  the area within which the plot and axes should be drawn
     *                  (<code>null not permitted).
     * @param dataArea  the area within which the data should be drawn
     *                  (<code>null not permitted).
     * @param edge  the axis location (<code>null not permitted).
     * @param plotState  collects information about the plot
     *                   (<code>null permitted).
     *
     * @return The axis state (never <code>null).
     */
    public AxisState draw(Graphics2D g2,
                          double cursor,
                          Rectangle2D plotArea,
                          Rectangle2D dataArea,
                          RectangleEdge edge,
                          PlotRenderingInfo plotState) {

        AxisState info = new AxisState(cursor);
        if (isVisible()) {
            info = super.draw(g2, cursor, plotArea, dataArea, edge, plotState);
        }
        if (this.gridBandsVisible) {
            drawGridBands(g2, plotArea, dataArea, edge, info.getTicks());
        }
        return info;

    }

    /**
     * Draws the grid bands.  Alternate bands are colored using
     * <CODE>gridBandPaint (DEFAULT_GRID_BAND_PAINT by
     * default).
     *
     * @param g2  the graphics device.
     * @param plotArea  the area within which the chart should be drawn.
     * @param dataArea  the area within which the plot should be drawn (a
     *                  subset of the drawArea).
     * @param edge  the axis location.
     * @param ticks  the ticks.
     */
    protected void drawGridBands(Graphics2D g2,
                                 Rectangle2D plotArea,
                                 Rectangle2D dataArea,
                                 RectangleEdge edge,
                                 List ticks) {

        Shape savedClip = g2.getClip();
        g2.clip(dataArea);
        if (RectangleEdge.isTopOrBottom(edge)) {
            drawGridBandsHorizontal(g2, plotArea, dataArea, true, ticks);
        }
        else if (RectangleEdge.isLeftOrRight(edge)) {
            drawGridBandsVertical(g2, plotArea, dataArea, true, ticks);
        }
        g2.setClip(savedClip);

    }

    /**
     * Draws the grid bands for the axis when it is at the top or bottom of
     * the plot.
     *
     * @param g2  the graphics device.
     * @param plotArea  the area within which the chart should be drawn.
     * @param dataArea  the area within which the plot should be drawn
     *                  (a subset of the drawArea).
     * @param firstGridBandIsDark  True: the first grid band takes the
     *                             color of <CODE>gridBandPaint.
     *                             False: the second grid band takes the
     *                             color of <CODE>gridBandPaint.
     * @param ticks  the ticks.
     */
    protected void drawGridBandsHorizontal(Graphics2D g2,
                                           Rectangle2D plotArea,
                                           Rectangle2D dataArea,
                                           boolean firstGridBandIsDark,
                                           List ticks) {

        boolean currentGridBandIsDark = firstGridBandIsDark;
        double yy = dataArea.getY();
        double xx1, xx2;

        //gets the outline stroke width of the plot
        double outlineStrokeWidth;
        if (getPlot().getOutlineStroke() !=  null) {
            outlineStrokeWidth
                = ((BasicStroke) getPlot().getOutlineStroke()).getLineWidth();
        }
        else {
            outlineStrokeWidth = 1d;
        }

        Iterator iterator = ticks.iterator();
        ValueTick tick;
        Rectangle2D band;
        while (iterator.hasNext()) {
            tick = (ValueTick) iterator.next();
            xx1 = valueToJava2D(tick.getValue() - 0.5d, dataArea,
                    RectangleEdge.BOTTOM);
            xx2 = valueToJava2D(tick.getValue() + 0.5d, dataArea,
                    RectangleEdge.BOTTOM);
            if (currentGridBandIsDark) {
                g2.setPaint(this.gridBandPaint);
            }
            else {
                g2.setPaint(this.gridBandAlternatePaint);
            }
            band = new Rectangle2D.Double(xx1, yy + outlineStrokeWidth,
                xx2 - xx1, dataArea.getMaxY() - yy - outlineStrokeWidth);
            g2.fill(band);
            currentGridBandIsDark = !currentGridBandIsDark;
        }
        g2.setPaintMode();
    }

    /**
     * Draws the grid bands for the axis when it is at the top or bottom of
     * the plot.
     *
     * @param g2  the graphics device.
     * @param drawArea  the area within which the chart should be drawn.
     * @param plotArea  the area within which the plot should be drawn (a
     *                  subset of the drawArea).
     * @param firstGridBandIsDark  True: the first grid band takes the
     *                             color of <CODE>gridBandPaint.
     *                             False: the second grid band takes the
     *                             color of <CODE>gridBandPaint.
     * @param ticks  a list of ticks.
     */
    protected void drawGridBandsVertical(Graphics2D g2,
                                         Rectangle2D drawArea,
                                         Rectangle2D plotArea,
                                         boolean firstGridBandIsDark,
                                         List ticks) {

        boolean currentGridBandIsDark = firstGridBandIsDark;
        double xx = plotArea.getX();
        double yy1, yy2;

        //gets the outline stroke width of the plot
        double outlineStrokeWidth;
        Stroke outlineStroke = getPlot().getOutlineStroke();
        if (outlineStroke != null && outlineStroke instanceof BasicStroke) {
            outlineStrokeWidth = ((BasicStroke) outlineStroke).getLineWidth();
        }
        else {
            outlineStrokeWidth = 1d;
        }

        Iterator iterator = ticks.iterator();
        ValueTick tick;
        Rectangle2D band;
        while (iterator.hasNext()) {
            tick = (ValueTick) iterator.next();
            yy1 = valueToJava2D(tick.getValue() + 0.5d, plotArea,
                    RectangleEdge.LEFT);
            yy2 = valueToJava2D(tick.getValue() - 0.5d, plotArea,
                    RectangleEdge.LEFT);
            if (currentGridBandIsDark) {
                g2.setPaint(this.gridBandPaint);
            }
            else {
                g2.setPaint(this.gridBandAlternatePaint);
            }
            band = new Rectangle2D.Double(xx + outlineStrokeWidth, yy1,
                    plotArea.getMaxX() - xx - outlineStrokeWidth, yy2 - yy1);
            g2.fill(band);
            currentGridBandIsDark = !currentGridBandIsDark;
        }
        g2.setPaintMode();
    }

    /**
     * Rescales the axis to ensure that all data is visible.
     */
    protected void autoAdjustRange() {

        Plot plot = getPlot();
        if (plot == null) {
            return;  // no plot, no data
        }

        if (plot instanceof ValueAxisPlot) {

            // ensure that all the symbols are displayed
            double upper = this.symbols.size() - 1;
            double lower = 0;
            double range = upper - lower;

            // ensure the autorange is at least <minRange> in size...
            double minRange = getAutoRangeMinimumSize();
            if (range < minRange) {
                upper = (upper + lower + minRange) / 2;
                lower = (upper + lower - minRange) / 2;
            }

            // this ensure that the grid bands will be displayed correctly.
            double upperMargin = 0.5;
            double lowerMargin = 0.5;

            if (getAutoRangeIncludesZero()) {
                if (getAutoRangeStickyZero()) {
                    if (upper <= 0.0) {
                        upper = 0.0;
                    }
                    else {
                        upper = upper + upperMargin;
                    }
                    if (lower >= 0.0) {
                        lower = 0.0;
                    }
                    else {
                        lower = lower - lowerMargin;
                    }
                }
                else {
                    upper = Math.max(0.0, upper + upperMargin);
                    lower = Math.min(0.0, lower - lowerMargin);
                }
            }
            else {
                if (getAutoRangeStickyZero()) {
                    if (upper <= 0.0) {
                        upper = Math.min(0.0, upper + upperMargin);
                    }
                    else {
                        upper = upper + upperMargin * range;
                    }
                    if (lower >= 0.0) {
                        lower = Math.max(0.0, lower - lowerMargin);
                    }
                    else {
                        lower = lower - lowerMargin;
                    }
                }
                else {
                    upper = upper + upperMargin;
                    lower = lower - lowerMargin;
                }
            }

            setRange(new Range(lower, upper), false, false);

        }

    }

    /**
     * Calculates the positions of the tick labels for the axis, storing the
     * results in the tick label list (ready for drawing).
     *
     * @param g2  the graphics device.
     * @param state  the axis state.
     * @param dataArea  the area in which the data should be drawn.
     * @param edge  the location of the axis.
     *
     * @return A list of ticks.
     */
    public List refreshTicks(Graphics2D g2,
                             AxisState state,
                             Rectangle2D dataArea,
                             RectangleEdge edge) {
        List ticks = null;
        if (RectangleEdge.isTopOrBottom(edge)) {
            ticks = refreshTicksHorizontal(g2, dataArea, edge);
        }
        else if (RectangleEdge.isLeftOrRight(edge)) {
            ticks = refreshTicksVertical(g2, dataArea, edge);
        }
        return ticks;
    }

    /**
     * Calculates the positions of the tick labels for the axis, storing the
     * results in the tick label list (ready for drawing).
     *
     * @param g2  the graphics device.
     * @param dataArea  the area in which the data should be drawn.
     * @param edge  the location of the axis.
     *
     * @return The ticks.
     */
    protected List refreshTicksHorizontal(Graphics2D g2,
                                          Rectangle2D dataArea,
                                          RectangleEdge edge) {

        List ticks = new java.util.ArrayList();

        Font tickLabelFont = getTickLabelFont();
        g2.setFont(tickLabelFont);

        double size = getTickUnit().getSize();
        int count = calculateVisibleTickCount();
        double lowestTickValue = calculateLowestVisibleTickValue();

        double previousDrawnTickLabelPos = 0.0;
        double previousDrawnTickLabelLength = 0.0;

        if (count <= ValueAxis.MAXIMUM_TICK_COUNT) {
            for (int i = 0; i < count; i++) {
                double currentTickValue = lowestTickValue + (i * size);
                double xx = valueToJava2D(currentTickValue, dataArea, edge);
                String tickLabel;
                NumberFormat formatter = getNumberFormatOverride();
                if (formatter != null) {
                    tickLabel = formatter.format(currentTickValue);
                }
                else {
                    tickLabel = valueToString(currentTickValue);
                }

                // avoid to draw overlapping tick labels
                Rectangle2D bounds = TextUtilities.getTextBounds(tickLabel, g2,
                        g2.getFontMetrics());
                double tickLabelLength = isVerticalTickLabels()
                        ? bounds.getHeight() : bounds.getWidth();
                boolean tickLabelsOverlapping = false;
                if (i > 0) {
                    double avgTickLabelLength = (previousDrawnTickLabelLength
                            + tickLabelLength) / 2.0;
                    if (Math.abs(xx - previousDrawnTickLabelPos)
                            < avgTickLabelLength) {
                        tickLabelsOverlapping = true;
                    }
                }
                if (tickLabelsOverlapping) {
                    tickLabel = ""; // don't draw this tick label
                }
                else {
                    // remember these values for next comparison
                    previousDrawnTickLabelPos = xx;
                    previousDrawnTickLabelLength = tickLabelLength;
                }

                TextAnchor anchor = null;
                TextAnchor rotationAnchor = null;
                double angle = 0.0;
                if (isVerticalTickLabels()) {
                    anchor = TextAnchor.CENTER_RIGHT;
                    rotationAnchor = TextAnchor.CENTER_RIGHT;
                    if (edge == RectangleEdge.TOP) {
                        angle = Math.PI / 2.0;
                    }
                    else {
                        angle = -Math.PI / 2.0;
                    }
                }
                else {
                    if (edge == RectangleEdge.TOP) {
                        anchor = TextAnchor.BOTTOM_CENTER;
                        rotationAnchor = TextAnchor.BOTTOM_CENTER;
                    }
                    else {
                        anchor = TextAnchor.TOP_CENTER;
                        rotationAnchor = TextAnchor.TOP_CENTER;
                    }
                }
                Tick tick = new NumberTick(new Double(currentTickValue),
                        tickLabel, anchor, rotationAnchor, angle);
                ticks.add(tick);
            }
        }
        return ticks;

    }

    /**
     * Calculates the positions of the tick labels for the axis, storing the
     * results in the tick label list (ready for drawing).
     *
     * @param g2  the graphics device.
     * @param dataArea  the area in which the plot should be drawn.
     * @param edge  the location of the axis.
     *
     * @return The ticks.
     */
    protected List refreshTicksVertical(Graphics2D g2,
                                        Rectangle2D dataArea,
                                        RectangleEdge edge) {

        List ticks = new java.util.ArrayList();

        Font tickLabelFont = getTickLabelFont();
        g2.setFont(tickLabelFont);

        double size = getTickUnit().getSize();
        int count = calculateVisibleTickCount();
        double lowestTickValue = calculateLowestVisibleTickValue();

        double previousDrawnTickLabelPos = 0.0;
        double previousDrawnTickLabelLength = 0.0;

        if (count <= ValueAxis.MAXIMUM_TICK_COUNT) {
            for (int i = 0; i < count; i++) {
                double currentTickValue = lowestTickValue + (i * size);
                double yy = valueToJava2D(currentTickValue, dataArea, edge);
                String tickLabel;
                NumberFormat formatter = getNumberFormatOverride();
                if (formatter != null) {
                    tickLabel = formatter.format(currentTickValue);
                }
                else {
                    tickLabel = valueToString(currentTickValue);
                }

                // avoid to draw overlapping tick labels
                Rectangle2D bounds = TextUtilities.getTextBounds(tickLabel, g2,
                        g2.getFontMetrics());
                double tickLabelLength = isVerticalTickLabels()
                    ? bounds.getWidth() : bounds.getHeight();
                boolean tickLabelsOverlapping = false;
                if (i > 0) {
                    double avgTickLabelLength = (previousDrawnTickLabelLength
                            + tickLabelLength) / 2.0;
                    if (Math.abs(yy - previousDrawnTickLabelPos)
                            < avgTickLabelLength) {
                        tickLabelsOverlapping = true;
                    }
                }
                if (tickLabelsOverlapping) {
                    tickLabel = ""; // don't draw this tick label
                }
                else {
                    // remember these values for next comparison
                    previousDrawnTickLabelPos = yy;
                    previousDrawnTickLabelLength = tickLabelLength;
                }

                TextAnchor anchor = null;
                TextAnchor rotationAnchor = null;
                double angle = 0.0;
                if (isVerticalTickLabels()) {
                    anchor = TextAnchor.BOTTOM_CENTER;
                    rotationAnchor = TextAnchor.BOTTOM_CENTER;
                    if (edge == RectangleEdge.LEFT) {
                        angle = -Math.PI / 2.0;
                    }
                    else {
                        angle = Math.PI / 2.0;
                    }
                }
                else {
                    if (edge == RectangleEdge.LEFT) {
                        anchor = TextAnchor.CENTER_RIGHT;
                        rotationAnchor = TextAnchor.CENTER_RIGHT;
                    }
                    else {
                        anchor = TextAnchor.CENTER_LEFT;
                        rotationAnchor = TextAnchor.CENTER_LEFT;
                    }
                }
                Tick tick = new NumberTick(new Double(currentTickValue),
                        tickLabel, anchor, rotationAnchor, angle);
                ticks.add(tick);
            }
        }
        return ticks;

    }

    /**
     * Converts a value to a string, using the list of symbols.
     *
     * @param value  value to convert.
     *
     * @return The symbol.
     */
    public String valueToString(double value) {
        String strToReturn;
        try {
            strToReturn = (String) this.symbols.get((int) value);
        }
        catch (IndexOutOfBoundsException  ex) {
            strToReturn = "";
        }
        return strToReturn;
    }

    /**
     * Tests this axis for equality with an arbitrary object.
     *
     * @param obj  the object (<code>null permitted).
     *
     * @return A boolean.
     */
    public boolean equals(Object obj) {
        if (obj == this) {
            return true;
        }
        if (!(obj instanceof SymbolAxis)) {
            return false;
        }
        SymbolAxis that = (SymbolAxis) obj;
        if (!this.symbols.equals(that.symbols)) {
            return false;
        }
        if (this.gridBandsVisible != that.gridBandsVisible) {
            return false;
        }
        if (!PaintUtilities.equal(this.gridBandPaint, that.gridBandPaint)) {
            return false;
        }
        if (!PaintUtilities.equal(this.gridBandAlternatePaint,
                that.gridBandAlternatePaint)) {
            return false;
        }
        return super.equals(obj);
    }

    /**
     * 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.writePaint(this.gridBandPaint, stream);
        SerialUtilities.writePaint(this.gridBandAlternatePaint, stream);
    }

    /**
     * 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.gridBandPaint = SerialUtilities.readPaint(stream);
        this.gridBandAlternatePaint = SerialUtilities.readPaint(stream);
    }

}