001    /* ===========================================================
002     * JFreeChart : a free chart library for the Java(tm) platform
003     * ===========================================================
004     *
005     * (C) Copyright 2000-2009, by Object Refinery Limited and Contributors.
006     *
007     * Project Info:  http://www.jfree.org/jfreechart/index.html
008     *
009     * This library is free software; you can redistribute it and/or modify it
010     * under the terms of the GNU Lesser General Public License as published by
011     * the Free Software Foundation; either version 2.1 of the License, or
012     * (at your option) any later version.
013     *
014     * This library is distributed in the hope that it will be useful, but
015     * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
016     * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
017     * License for more details.
018     *
019     * You should have received a copy of the GNU Lesser General Public
020     * License along with this library; if not, write to the Free Software
021     * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
022     * USA.
023     *
024     * [Java is a trademark or registered trademark of Sun Microsystems, Inc.
025     * in the United States and other countries.]
026     *
027     * ------------
028     * LogAxis.java
029     * ------------
030     * (C) Copyright 2006-2009, by Object Refinery Limited and Contributors.
031     *
032     * Original Author:  David Gilbert (for Object Refinery Limited);
033     * Contributor(s):   Andrew Mickish (patch 1868745);
034     *                   Peter Kolb (patches 1934255 and 2603321);
035     *
036     * Changes
037     * -------
038     * 24-Aug-2006 : Version 1 (DG);
039     * 22-Mar-2007 : Use defaultAutoArrange attribute (DG);
040     * 02-Aug-2007 : Fixed zooming bug, added support for margins (DG);
041     * 14-Feb-2008 : Changed default minorTickCount to 9 - see bug report
042     *               1892419 (DG);
043     * 15-Feb-2008 : Applied a variation of patch 1868745 by Andrew Mickish to
044     *               fix a labelling bug when the axis appears at the top or
045     *               right of the chart (DG);
046     * 19-Mar-2008 : Applied patch 1902418 by Andrew Mickish to fix bug in tick
047     *               labels for vertical axis (DG);
048     * 26-Mar-2008 : Changed createTickLabel() method from private to protected -
049     *               see patch 1918209 by Andrew Mickish (DG);
050     * 25-Sep-2008 : Moved minor tick fields up to superclass, see patch 1934255
051     *               by Peter Kolb (DG);
052     * 14-Jan-2009 : Fetch minor ticks from TickUnit, and corrected
053     *               createLogTickUnits() (DG);
054     * 21-Jan-2009 : No need to call setMinorTickCount() in constructor (DG);
055     * 19-Mar-2009 : Added entity support - see patch 2603321 by Peter Kolb (DG);
056     * 30-Mar-2009 : Added pan(double) method (DG);
057     *
058     */
059    
060    package org.jfree.chart.axis;
061    
062    import java.awt.Font;
063    import java.awt.FontMetrics;
064    import java.awt.Graphics2D;
065    import java.awt.font.FontRenderContext;
066    import java.awt.font.LineMetrics;
067    import java.awt.geom.Rectangle2D;
068    import java.text.DecimalFormat;
069    import java.text.NumberFormat;
070    import java.util.ArrayList;
071    import java.util.List;
072    import java.util.Locale;
073    
074    import org.jfree.chart.event.AxisChangeEvent;
075    import org.jfree.chart.plot.Plot;
076    import org.jfree.chart.plot.PlotRenderingInfo;
077    import org.jfree.chart.plot.ValueAxisPlot;
078    import org.jfree.chart.util.LogFormat;
079    import org.jfree.data.Range;
080    import org.jfree.ui.RectangleEdge;
081    import org.jfree.ui.RectangleInsets;
082    import org.jfree.ui.TextAnchor;
083    
084    /**
085     * A numerical axis that uses a logarithmic scale.  The class is an
086     * alternative to the {@link LogarithmicAxis} class.
087     *
088     * @since 1.0.7
089     */
090    public class LogAxis extends ValueAxis {
091    
092        /** The logarithm base. */
093        private double base = 10.0;
094    
095        /** The logarithm of the base value - cached for performance. */
096        private double baseLog = Math.log(10.0);
097    
098        /**  The smallest value permitted on the axis. */
099        private double smallestValue = 1E-100;
100    
101        /** The current tick unit. */
102        private NumberTickUnit tickUnit;
103    
104        /** The override number format. */
105        private NumberFormat numberFormatOverride;
106    
107        /**
108         * Creates a new <code>LogAxis</code> with no label.
109         */
110        public LogAxis() {
111            this(null);
112        }
113    
114        /**
115         * Creates a new <code>LogAxis</code> with the given label.
116         *
117         * @param label  the axis label (<code>null</code> permitted).
118         */
119        public LogAxis(String label) {
120            super(label, createLogTickUnits(Locale.getDefault()));
121            setDefaultAutoRange(new Range(0.01, 1.0));
122            this.tickUnit = new NumberTickUnit(1.0, new DecimalFormat("0.#"), 9);
123        }
124    
125        /**
126         * Returns the base for the logarithm calculation.
127         *
128         * @return The base for the logarithm calculation.
129         *
130         * @see #setBase(double)
131         */
132        public double getBase() {
133            return this.base;
134        }
135    
136        /**
137         * Sets the base for the logarithm calculation and sends an
138         * {@link AxisChangeEvent} to all registered listeners.
139         *
140         * @param base  the base value (must be > 1.0).
141         *
142         * @see #getBase()
143         */
144        public void setBase(double base) {
145            if (base <= 1.0) {
146                throw new IllegalArgumentException("Requires 'base' > 1.0.");
147            }
148            this.base = base;
149            this.baseLog = Math.log(base);
150            notifyListeners(new AxisChangeEvent(this));
151        }
152    
153        /**
154         * Returns the smallest value represented by the axis.
155         *
156         * @return The smallest value represented by the axis.
157         *
158         * @see #setSmallestValue(double)
159         */
160        public double getSmallestValue() {
161            return this.smallestValue;
162        }
163    
164        /**
165         * Sets the smallest value represented by the axis and sends an
166         * {@link AxisChangeEvent} to all registered listeners.
167         *
168         * @param value  the value.
169         *
170         * @see #getSmallestValue()
171         */
172        public void setSmallestValue(double value) {
173            if (value <= 0.0) {
174                throw new IllegalArgumentException("Requires 'value' > 0.0.");
175            }
176            this.smallestValue = value;
177            notifyListeners(new AxisChangeEvent(this));
178        }
179    
180        /**
181         * Returns the current tick unit.
182         *
183         * @return The current tick unit.
184         *
185         * @see #setTickUnit(NumberTickUnit)
186         */
187        public NumberTickUnit getTickUnit() {
188            return this.tickUnit;
189        }
190    
191        /**
192         * Sets the tick unit for the axis and sends an {@link AxisChangeEvent} to
193         * all registered listeners.  A side effect of calling this method is that
194         * the "auto-select" feature for tick units is switched off (you can
195         * restore it using the {@link ValueAxis#setAutoTickUnitSelection(boolean)}
196         * method).
197         *
198         * @param unit  the new tick unit (<code>null</code> not permitted).
199         *
200         * @see #getTickUnit()
201         */
202        public void setTickUnit(NumberTickUnit unit) {
203            // defer argument checking...
204            setTickUnit(unit, true, true);
205        }
206    
207        /**
208         * Sets the tick unit for the axis and, if requested, sends an
209         * {@link AxisChangeEvent} to all registered listeners.  In addition, an
210         * option is provided to turn off the "auto-select" feature for tick units
211         * (you can restore it using the
212         * {@link ValueAxis#setAutoTickUnitSelection(boolean)} method).
213         *
214         * @param unit  the new tick unit (<code>null</code> not permitted).
215         * @param notify  notify listeners?
216         * @param turnOffAutoSelect  turn off the auto-tick selection?
217         *
218         * @see #getTickUnit()
219         */
220        public void setTickUnit(NumberTickUnit unit, boolean notify,
221                                boolean turnOffAutoSelect) {
222    
223            if (unit == null) {
224                throw new IllegalArgumentException("Null 'unit' argument.");
225            }
226            this.tickUnit = unit;
227            if (turnOffAutoSelect) {
228                setAutoTickUnitSelection(false, false);
229            }
230            if (notify) {
231                notifyListeners(new AxisChangeEvent(this));
232            }
233    
234        }
235    
236        /**
237         * Returns the number format override.  If this is non-null, then it will
238         * be used to format the numbers on the axis.
239         *
240         * @return The number formatter (possibly <code>null</code>).
241         *
242         * @see #setNumberFormatOverride(NumberFormat)
243         */
244        public NumberFormat getNumberFormatOverride() {
245            return this.numberFormatOverride;
246        }
247    
248        /**
249         * Sets the number format override.  If this is non-null, then it will be
250         * used to format the numbers on the axis.
251         *
252         * @param formatter  the number formatter (<code>null</code> permitted).
253         *
254         * @see #getNumberFormatOverride()
255         */
256        public void setNumberFormatOverride(NumberFormat formatter) {
257            this.numberFormatOverride = formatter;
258            notifyListeners(new AxisChangeEvent(this));
259        }
260    
261        /**
262         * Calculates the log of the given value, using the current base.
263         *
264         * @param value  the value.
265         *
266         * @return The log of the given value.
267         *
268         * @see #calculateValue(double)
269         * @see #getBase()
270         */
271        public double calculateLog(double value) {
272            return Math.log(value) / this.baseLog;
273        }
274    
275        /**
276         * Calculates the value from a given log.
277         *
278         * @param log  the log value (must be > 0.0).
279         *
280         * @return The value with the given log.
281         *
282         * @see #calculateLog(double)
283         * @see #getBase()
284         */
285        public double calculateValue(double log) {
286            return Math.pow(this.base, log);
287        }
288    
289        /**
290         * Converts a Java2D coordinate to an axis value, assuming that the
291         * axis covers the specified <code>edge</code> of the <code>area</code>.
292         *
293         * @param java2DValue  the Java2D coordinate.
294         * @param area  the area.
295         * @param edge  the edge that the axis belongs to.
296         *
297         * @return A value along the axis scale.
298         */
299        public double java2DToValue(double java2DValue, Rectangle2D area,
300                RectangleEdge edge) {
301    
302            Range range = getRange();
303            double axisMin = calculateLog(range.getLowerBound());
304            double axisMax = calculateLog(range.getUpperBound());
305    
306            double min = 0.0;
307            double max = 0.0;
308            if (RectangleEdge.isTopOrBottom(edge)) {
309                min = area.getX();
310                max = area.getMaxX();
311            }
312            else if (RectangleEdge.isLeftOrRight(edge)) {
313                min = area.getMaxY();
314                max = area.getY();
315            }
316            double log = 0.0;
317            if (isInverted()) {
318                log = axisMax - (java2DValue - min) / (max - min)
319                        * (axisMax - axisMin);
320            }
321            else {
322                log = axisMin + (java2DValue - min) / (max - min)
323                        * (axisMax - axisMin);
324            }
325            return calculateValue(log);
326        }
327    
328        /**
329         * Converts a value on the axis scale to a Java2D coordinate relative to
330         * the given <code>area</code>, based on the axis running along the
331         * specified <code>edge</code>.
332         *
333         * @param value  the data value.
334         * @param area  the area.
335         * @param edge  the edge.
336         *
337         * @return The Java2D coordinate corresponding to <code>value</code>.
338         */
339        public double valueToJava2D(double value, Rectangle2D area,
340                RectangleEdge edge) {
341    
342            Range range = getRange();
343            double axisMin = calculateLog(range.getLowerBound());
344            double axisMax = calculateLog(range.getUpperBound());
345            value = calculateLog(value);
346    
347            double min = 0.0;
348            double max = 0.0;
349            if (RectangleEdge.isTopOrBottom(edge)) {
350                min = area.getX();
351                max = area.getMaxX();
352            }
353            else if (RectangleEdge.isLeftOrRight(edge)) {
354                max = area.getMinY();
355                min = area.getMaxY();
356            }
357            if (isInverted()) {
358                return max
359                       - ((value - axisMin) / (axisMax - axisMin)) * (max - min);
360            }
361            else {
362                return min
363                       + ((value - axisMin) / (axisMax - axisMin)) * (max - min);
364            }
365        }
366    
367        /**
368         * Configures the axis.  This method is typically called when an axis
369         * is assigned to a new plot.
370         */
371        public void configure() {
372            if (isAutoRange()) {
373                autoAdjustRange();
374            }
375        }
376    
377        /**
378         * Adjusts the axis range to match the data range that the axis is
379         * required to display.
380         */
381        protected void autoAdjustRange() {
382            Plot plot = getPlot();
383            if (plot == null) {
384                return;  // no plot, no data
385            }
386    
387            if (plot instanceof ValueAxisPlot) {
388                ValueAxisPlot vap = (ValueAxisPlot) plot;
389    
390                Range r = vap.getDataRange(this);
391                if (r == null) {
392                    r = getDefaultAutoRange();
393                }
394    
395                double upper = r.getUpperBound();
396                double lower = Math.max(r.getLowerBound(), this.smallestValue);
397                double range = upper - lower;
398    
399                // if fixed auto range, then derive lower bound...
400                double fixedAutoRange = getFixedAutoRange();
401                if (fixedAutoRange > 0.0) {
402                    lower = Math.max(upper - fixedAutoRange, this.smallestValue);
403                }
404                else {
405                    // ensure the autorange is at least <minRange> in size...
406                    double minRange = getAutoRangeMinimumSize();
407                    if (range < minRange) {
408                        double expand = (minRange - range) / 2;
409                        upper = upper + expand;
410                        lower = lower - expand;
411                    }
412    
413                    // apply the margins - these should apply to the exponent range
414                    double logUpper = calculateLog(upper);
415                    double logLower = calculateLog(lower);
416                    double logRange = logUpper - logLower;
417                    logUpper = logUpper + getUpperMargin() * logRange;
418                    logLower = logLower - getLowerMargin() * logRange;
419                    upper = calculateValue(logUpper);
420                    lower = calculateValue(logLower);
421                }
422    
423                setRange(new Range(lower, upper), false, false);
424            }
425    
426        }
427    
428        /**
429         * Draws the axis on a Java 2D graphics device (such as the screen or a
430         * printer).
431         *
432         * @param g2  the graphics device (<code>null</code> not permitted).
433         * @param cursor  the cursor location (determines where to draw the axis).
434         * @param plotArea  the area within which the axes and plot should be drawn.
435         * @param dataArea  the area within which the data should be drawn.
436         * @param edge  the axis location (<code>null</code> not permitted).
437         * @param plotState  collects information about the plot
438         *                   (<code>null</code> permitted).
439         *
440         * @return The axis state (never <code>null</code>).
441         */
442        public AxisState draw(Graphics2D g2, double cursor, Rectangle2D plotArea,
443                Rectangle2D dataArea, RectangleEdge edge,
444                PlotRenderingInfo plotState) {
445    
446            AxisState state = null;
447            // if the axis is not visible, don't draw it...
448            if (!isVisible()) {
449                state = new AxisState(cursor);
450                // even though the axis is not visible, we need ticks for the
451                // gridlines...
452                List ticks = refreshTicks(g2, state, dataArea, edge);
453                state.setTicks(ticks);
454                return state;
455            }
456            state = drawTickMarksAndLabels(g2, cursor, plotArea, dataArea, edge);
457            state = drawLabel(getLabel(), g2, plotArea, dataArea, edge, state);
458            createAndAddEntity(cursor, state, dataArea, edge, plotState);
459            return state;
460        }
461    
462        /**
463         * Calculates the positions of the tick labels for the axis, storing the
464         * results in the tick label list (ready for drawing).
465         *
466         * @param g2  the graphics device.
467         * @param state  the axis state.
468         * @param dataArea  the area in which the plot should be drawn.
469         * @param edge  the location of the axis.
470         *
471         * @return A list of ticks.
472         *
473         */
474        public List refreshTicks(Graphics2D g2, AxisState state,
475                Rectangle2D dataArea, RectangleEdge edge) {
476    
477            List result = new java.util.ArrayList();
478            if (RectangleEdge.isTopOrBottom(edge)) {
479                result = refreshTicksHorizontal(g2, dataArea, edge);
480            }
481            else if (RectangleEdge.isLeftOrRight(edge)) {
482                result = refreshTicksVertical(g2, dataArea, edge);
483            }
484            return result;
485    
486        }
487    
488        /**
489         * Returns a list of ticks for an axis at the top or bottom of the chart.
490         *
491         * @param g2  the graphics device.
492         * @param dataArea  the data area.
493         * @param edge  the edge.
494         *
495         * @return A list of ticks.
496         */
497        protected List refreshTicksHorizontal(Graphics2D g2, Rectangle2D dataArea,
498                RectangleEdge edge) {
499    
500            Range range = getRange();
501            List ticks = new ArrayList();
502            Font tickLabelFont = getTickLabelFont();
503            g2.setFont(tickLabelFont);
504            TextAnchor textAnchor;
505            if (edge == RectangleEdge.TOP) {
506                textAnchor = TextAnchor.BOTTOM_CENTER;
507            }
508            else {
509                textAnchor = TextAnchor.TOP_CENTER;
510            }
511    
512            if (isAutoTickUnitSelection()) {
513                selectAutoTickUnit(g2, dataArea, edge);
514            }
515            int minorTickCount = this.tickUnit.getMinorTickCount();
516            double start = Math.floor(calculateLog(getLowerBound()));
517            double end = Math.ceil(calculateLog(getUpperBound()));
518            double current = start;
519            while (current <= end) {
520                double v = calculateValue(current);
521                if (range.contains(v)) {
522                    ticks.add(new NumberTick(TickType.MAJOR, v, createTickLabel(v),
523                            textAnchor, TextAnchor.CENTER, 0.0));
524                }
525                // add minor ticks (for gridlines)
526                double next = Math.pow(this.base, current
527                        + this.tickUnit.getSize());
528                for (int i = 1; i < minorTickCount; i++) {
529                    double minorV = v + i * ((next - v) / minorTickCount);
530                    if (range.contains(minorV)) {
531                        ticks.add(new NumberTick(TickType.MINOR, minorV, "",
532                                textAnchor, TextAnchor.CENTER, 0.0));
533                    }
534                }
535                current = current + this.tickUnit.getSize();
536            }
537            return ticks;
538        }
539    
540        /**
541         * Returns a list of ticks for an axis at the left or right of the chart.
542         *
543         * @param g2  the graphics device.
544         * @param dataArea  the data area.
545         * @param edge  the edge.
546         *
547         * @return A list of ticks.
548         */
549        protected List refreshTicksVertical(Graphics2D g2, Rectangle2D dataArea,
550                RectangleEdge edge) {
551    
552            Range range = getRange();
553            List ticks = new ArrayList();
554            Font tickLabelFont = getTickLabelFont();
555            g2.setFont(tickLabelFont);
556            TextAnchor textAnchor;
557            if (edge == RectangleEdge.RIGHT) {
558                textAnchor = TextAnchor.CENTER_LEFT;
559            }
560            else {
561                textAnchor = TextAnchor.CENTER_RIGHT;
562            }
563    
564            if (isAutoTickUnitSelection()) {
565                selectAutoTickUnit(g2, dataArea, edge);
566            }
567            int minorTickCount = this.tickUnit.getMinorTickCount();
568            double start = Math.floor(calculateLog(getLowerBound()));
569            double end = Math.ceil(calculateLog(getUpperBound()));
570            double current = start;
571            while (current <= end) {
572                double v = calculateValue(current);
573                if (range.contains(v)) {
574                    ticks.add(new NumberTick(TickType.MAJOR, v, createTickLabel(v),
575                            textAnchor, TextAnchor.CENTER, 0.0));
576                }
577                // add minor ticks (for gridlines)
578                double next = Math.pow(this.base, current
579                        + this.tickUnit.getSize());
580                for (int i = 1; i < minorTickCount; i++) {
581                    double minorV = v + i * ((next - v) / minorTickCount);
582                    if (range.contains(minorV)) {
583                        ticks.add(new NumberTick(TickType.MINOR, minorV, "",
584                                textAnchor, TextAnchor.CENTER, 0.0));
585                    }
586                }
587                current = current + this.tickUnit.getSize();
588            }
589            return ticks;
590        }
591    
592        /**
593         * Selects an appropriate tick value for the axis.  The strategy is to
594         * display as many ticks as possible (selected from an array of 'standard'
595         * tick units) without the labels overlapping.
596         *
597         * @param g2  the graphics device.
598         * @param dataArea  the area defined by the axes.
599         * @param edge  the axis location.
600         *
601         * @since 1.0.7
602         */
603        protected void selectAutoTickUnit(Graphics2D g2, Rectangle2D dataArea,
604                RectangleEdge edge) {
605    
606            if (RectangleEdge.isTopOrBottom(edge)) {
607                selectHorizontalAutoTickUnit(g2, dataArea, edge);
608            }
609            else if (RectangleEdge.isLeftOrRight(edge)) {
610                selectVerticalAutoTickUnit(g2, dataArea, edge);
611            }
612    
613        }
614    
615        /**
616         * Selects an appropriate tick value for the axis.  The strategy is to
617         * display as many ticks as possible (selected from an array of 'standard'
618         * tick units) without the labels overlapping.
619         *
620         * @param g2  the graphics device.
621         * @param dataArea  the area defined by the axes.
622         * @param edge  the axis location.
623         *
624         * @since 1.0.7
625         */
626       protected void selectHorizontalAutoTickUnit(Graphics2D g2,
627               Rectangle2D dataArea, RectangleEdge edge) {
628    
629            double tickLabelWidth = estimateMaximumTickLabelWidth(g2,
630                    getTickUnit());
631    
632            // start with the current tick unit...
633            TickUnitSource tickUnits = getStandardTickUnits();
634            TickUnit unit1 = tickUnits.getCeilingTickUnit(getTickUnit());
635            double unit1Width = exponentLengthToJava2D(unit1.getSize(), dataArea,
636                    edge);
637    
638            // then extrapolate...
639            double guess = (tickLabelWidth / unit1Width) * unit1.getSize();
640    
641            NumberTickUnit unit2 = (NumberTickUnit)
642                    tickUnits.getCeilingTickUnit(guess);
643            double unit2Width = exponentLengthToJava2D(unit2.getSize(), dataArea,
644                    edge);
645    
646            tickLabelWidth = estimateMaximumTickLabelWidth(g2, unit2);
647            if (tickLabelWidth > unit2Width) {
648                unit2 = (NumberTickUnit) tickUnits.getLargerTickUnit(unit2);
649            }
650    
651            setTickUnit(unit2, false, false);
652    
653        }
654    
655        /**
656         * Converts a length in data coordinates into the corresponding length in
657         * Java2D coordinates.
658         *
659         * @param length  the length.
660         * @param area  the plot area.
661         * @param edge  the edge along which the axis lies.
662         *
663         * @return The length in Java2D coordinates.
664         *
665         * @since 1.0.7
666         */
667        public double exponentLengthToJava2D(double length, Rectangle2D area,
668                                    RectangleEdge edge) {
669            double one = valueToJava2D(calculateValue(1.0), area, edge);
670            double l = valueToJava2D(calculateValue(length + 1.0), area, edge);
671            return Math.abs(l - one);
672        }
673    
674        /**
675         * Selects an appropriate tick value for the axis.  The strategy is to
676         * display as many ticks as possible (selected from an array of 'standard'
677         * tick units) without the labels overlapping.
678         *
679         * @param g2  the graphics device.
680         * @param dataArea  the area in which the plot should be drawn.
681         * @param edge  the axis location.
682         *
683         * @since 1.0.7
684         */
685        protected void selectVerticalAutoTickUnit(Graphics2D g2,
686                                                  Rectangle2D dataArea,
687                                                  RectangleEdge edge) {
688    
689            double tickLabelHeight = estimateMaximumTickLabelHeight(g2);
690    
691            // start with the current tick unit...
692            TickUnitSource tickUnits = getStandardTickUnits();
693            TickUnit unit1 = tickUnits.getCeilingTickUnit(getTickUnit());
694            double unitHeight = exponentLengthToJava2D(unit1.getSize(), dataArea,
695                    edge);
696    
697            // then extrapolate...
698            double guess = (tickLabelHeight / unitHeight) * unit1.getSize();
699    
700            NumberTickUnit unit2 = (NumberTickUnit)
701                    tickUnits.getCeilingTickUnit(guess);
702            double unit2Height = exponentLengthToJava2D(unit2.getSize(), dataArea,
703                    edge);
704    
705            tickLabelHeight = estimateMaximumTickLabelHeight(g2);
706            if (tickLabelHeight > unit2Height) {
707                unit2 = (NumberTickUnit) tickUnits.getLargerTickUnit(unit2);
708            }
709    
710            setTickUnit(unit2, false, false);
711    
712        }
713    
714        /**
715         * Estimates the maximum tick label height.
716         *
717         * @param g2  the graphics device.
718         *
719         * @return The maximum height.
720         *
721         * @since 1.0.7
722         */
723        protected double estimateMaximumTickLabelHeight(Graphics2D g2) {
724    
725            RectangleInsets tickLabelInsets = getTickLabelInsets();
726            double result = tickLabelInsets.getTop() + tickLabelInsets.getBottom();
727    
728            Font tickLabelFont = getTickLabelFont();
729            FontRenderContext frc = g2.getFontRenderContext();
730            result += tickLabelFont.getLineMetrics("123", frc).getHeight();
731            return result;
732    
733        }
734    
735        /**
736         * Estimates the maximum width of the tick labels, assuming the specified
737         * tick unit is used.
738         * <P>
739         * Rather than computing the string bounds of every tick on the axis, we
740         * just look at two values: the lower bound and the upper bound for the
741         * axis.  These two values will usually be representative.
742         *
743         * @param g2  the graphics device.
744         * @param unit  the tick unit to use for calculation.
745         *
746         * @return The estimated maximum width of the tick labels.
747         *
748         * @since 1.0.7
749         */
750        protected double estimateMaximumTickLabelWidth(Graphics2D g2,
751                                                       TickUnit unit) {
752    
753            RectangleInsets tickLabelInsets = getTickLabelInsets();
754            double result = tickLabelInsets.getLeft() + tickLabelInsets.getRight();
755    
756            if (isVerticalTickLabels()) {
757                // all tick labels have the same width (equal to the height of the
758                // font)...
759                FontRenderContext frc = g2.getFontRenderContext();
760                LineMetrics lm = getTickLabelFont().getLineMetrics("0", frc);
761                result += lm.getHeight();
762            }
763            else {
764                // look at lower and upper bounds...
765                FontMetrics fm = g2.getFontMetrics(getTickLabelFont());
766                Range range = getRange();
767                double lower = range.getLowerBound();
768                double upper = range.getUpperBound();
769                String lowerStr = "";
770                String upperStr = "";
771                NumberFormat formatter = getNumberFormatOverride();
772                if (formatter != null) {
773                    lowerStr = formatter.format(lower);
774                    upperStr = formatter.format(upper);
775                }
776                else {
777                    lowerStr = unit.valueToString(lower);
778                    upperStr = unit.valueToString(upper);
779                }
780                double w1 = fm.stringWidth(lowerStr);
781                double w2 = fm.stringWidth(upperStr);
782                result += Math.max(w1, w2);
783            }
784    
785            return result;
786    
787        }
788    
789        /**
790         * Zooms in on the current range.
791         *
792         * @param lowerPercent  the new lower bound.
793         * @param upperPercent  the new upper bound.
794         */
795        public void zoomRange(double lowerPercent, double upperPercent) {
796            Range range = getRange();
797            double start = range.getLowerBound();
798            double end = range.getUpperBound();
799            double log1 = calculateLog(start);
800            double log2 = calculateLog(end);
801            double length = log2 - log1;
802            Range adjusted = null;
803            if (isInverted()) {
804                double logA = log1 + length * (1 - upperPercent);
805                double logB = log1 + length * (1 - lowerPercent);
806                adjusted = new Range(calculateValue(logA), calculateValue(logB));
807            }
808            else {
809                double logA = log1 + length * lowerPercent;
810                double logB = log1 + length * upperPercent;
811                adjusted = new Range(calculateValue(logA), calculateValue(logB));
812            }
813            setRange(adjusted);
814        }
815    
816        /**
817         * Slides the axis range by the specified percentage.
818         *
819         * @param percent  the percentage.
820         *
821         * @since 1.0.13
822         */
823        public void pan(double percent) {
824            Range range = getRange();
825            double lower = range.getLowerBound();
826            double upper = range.getUpperBound();
827            double log1 = calculateLog(lower);
828            double log2 = calculateLog(upper);
829            double length = log2 - log1;
830            double adj = length * percent;
831            log1 = log1 + adj;
832            log2 = log2 + adj;
833            setRange(calculateValue(log1), calculateValue(log2));
834        }
835    
836        /**
837         * Creates a tick label for the specified value.  Note that this method
838         * was 'private' prior to version 1.0.10.
839         *
840         * @param value  the value.
841         *
842         * @return The label.
843         *
844         * @since 1.0.10
845         */
846        protected String createTickLabel(double value) {
847            if (this.numberFormatOverride != null) {
848                return this.numberFormatOverride.format(value);
849            }
850            else {
851                return this.tickUnit.valueToString(value);
852            }
853        }
854    
855        /**
856         * Tests this axis for equality with an arbitrary object.
857         *
858         * @param obj  the object (<code>null</code> permitted).
859         *
860         * @return A boolean.
861         */
862        public boolean equals(Object obj) {
863            if (obj == this) {
864                return true;
865            }
866            if (!(obj instanceof LogAxis)) {
867                return false;
868            }
869            LogAxis that = (LogAxis) obj;
870            if (this.base != that.base) {
871                return false;
872            }
873            if (this.smallestValue != that.smallestValue) {
874                return false;
875            }
876            return super.equals(obj);
877        }
878    
879        /**
880         * Returns a hash code for this instance.
881         *
882         * @return A hash code.
883         */
884        public int hashCode() {
885            int result = 193;
886            long temp = Double.doubleToLongBits(this.base);
887            result = 37 * result + (int) (temp ^ (temp >>> 32));
888            temp = Double.doubleToLongBits(this.smallestValue);
889            result = 37 * result + (int) (temp ^ (temp >>> 32));
890            if (this.numberFormatOverride != null) {
891                result = 37 * result + this.numberFormatOverride.hashCode();
892            }
893            result = 37 * result + this.tickUnit.hashCode();
894            return result;
895        }
896    
897        /**
898         * Returns a collection of tick units for log (base 10) values.
899         * Uses a given Locale to create the DecimalFormats.
900         *
901         * @param locale the locale to use to represent Numbers.
902         *
903         * @return A collection of tick units for integer values.
904         *
905         * @since 1.0.7
906         */
907        public static TickUnitSource createLogTickUnits(Locale locale) {
908            TickUnits units = new TickUnits();
909            NumberFormat numberFormat = new LogFormat();
910            units.add(new NumberTickUnit(0.05, numberFormat, 2));
911            units.add(new NumberTickUnit(0.1, numberFormat, 10));
912            units.add(new NumberTickUnit(0.2, numberFormat, 2));
913            units.add(new NumberTickUnit(0.5, numberFormat, 5));
914            units.add(new NumberTickUnit(1, numberFormat, 10));
915            units.add(new NumberTickUnit(2, numberFormat, 10));
916            units.add(new NumberTickUnit(3, numberFormat, 15));
917            units.add(new NumberTickUnit(4, numberFormat, 20));
918            units.add(new NumberTickUnit(5, numberFormat, 25));
919            units.add(new NumberTickUnit(6, numberFormat));
920            units.add(new NumberTickUnit(7, numberFormat));
921            units.add(new NumberTickUnit(8, numberFormat));
922            units.add(new NumberTickUnit(9, numberFormat));
923            units.add(new NumberTickUnit(10, numberFormat));
924            return units;
925        }
926    
927    }