dateaxis.java

来自「JfreeChart 常用图表例子」· Java 代码 · 共 1,787 行 · 第 1/5 页

                DateTickUnit.MINUTE, 20, DateTickUnit.MINUTE, 5, f3
            )
        );
        units.add(
            new DateTickUnit(
                DateTickUnit.MINUTE, 30, DateTickUnit.MINUTE, 5, f3
            )
        );

        // hours
        units.add(
            new DateTickUnit(DateTickUnit.HOUR, 1, DateTickUnit.MINUTE, 5, f3)
        );
        units.add(
            new DateTickUnit(DateTickUnit.HOUR, 2, DateTickUnit.MINUTE, 10, f3)
        );
        units.add(
            new DateTickUnit(DateTickUnit.HOUR, 4, DateTickUnit.MINUTE, 30, f3)
        );
        units.add(
            new DateTickUnit(DateTickUnit.HOUR, 6, DateTickUnit.HOUR, 1, f3)
        );
        units.add(
            new DateTickUnit(DateTickUnit.HOUR, 12, DateTickUnit.HOUR, 1, f4)
        );

        // days
        units.add(
            new DateTickUnit(DateTickUnit.DAY, 1, DateTickUnit.HOUR, 1, f5)
        );
        units.add(
            new DateTickUnit(DateTickUnit.DAY, 2, DateTickUnit.HOUR, 1, f5)
        );
        units.add(
            new DateTickUnit(DateTickUnit.DAY, 7, DateTickUnit.DAY, 1, f5)
        );
        units.add(
            new DateTickUnit(DateTickUnit.DAY, 15, DateTickUnit.DAY, 1, f5)
        );

        // months
        units.add(
            new DateTickUnit(DateTickUnit.MONTH, 1, DateTickUnit.DAY, 1, f6)
        );
        units.add(
            new DateTickUnit(DateTickUnit.MONTH, 2, DateTickUnit.DAY, 1, f6)
        );
        units.add(
            new DateTickUnit(DateTickUnit.MONTH, 3, DateTickUnit.MONTH, 1, f6)
        );
        units.add(
            new DateTickUnit(DateTickUnit.MONTH, 4,  DateTickUnit.MONTH, 1, f6)
        );
        units.add(
            new DateTickUnit(DateTickUnit.MONTH, 6,  DateTickUnit.MONTH, 1, f6)
        );

        // years
        units.add(
            new DateTickUnit(DateTickUnit.YEAR, 1,  DateTickUnit.MONTH, 1, f7)
        );
        units.add(
            new DateTickUnit(DateTickUnit.YEAR, 2,  DateTickUnit.MONTH, 3, f7)
        );
        units.add(
            new DateTickUnit(DateTickUnit.YEAR, 5,  DateTickUnit.YEAR, 1, f7)
        );
        units.add(
            new DateTickUnit(DateTickUnit.YEAR, 10,  DateTickUnit.YEAR, 1, f7)
        );
        units.add(
            new DateTickUnit(DateTickUnit.YEAR, 25, DateTickUnit.YEAR, 5, f7)
        );
        units.add(
            new DateTickUnit(DateTickUnit.YEAR, 50, DateTickUnit.YEAR, 10, f7)
        );
        units.add(
            new DateTickUnit(DateTickUnit.YEAR, 100, DateTickUnit.YEAR, 20, f7)
        );

        return units;

    }

    /**
     * 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) {
            ValueAxisPlot vap = (ValueAxisPlot) plot;

            Range r = vap.getDataRange(this);
            if (r == null) {
                if (this.timeline instanceof SegmentedTimeline) { 
                    //Timeline hasn't method getStartTime()
                    r = new DateRange(
                        ((SegmentedTimeline) this.timeline).getStartTime(),
                        ((SegmentedTimeline) this.timeline).getStartTime() + 1
                    );
                } 
                else {
                    r = new DateRange();
                }
            }

            long upper = this.timeline.toTimelineValue(
                (long) r.getUpperBound()
            );
            long lower;
            long fixedAutoRange = (long) getFixedAutoRange();
            if (fixedAutoRange > 0.0) {
                lower = upper - fixedAutoRange;
            }
            else {
                lower = this.timeline.toTimelineValue((long) r.getLowerBound());
                double range = upper - lower;
                long minRange = (long) getAutoRangeMinimumSize();
                if (range < minRange) {
                    long expand = (long) (minRange - range) / 2;
                    upper = upper + expand;
                    lower = lower - expand;
                }
                upper = upper + (long) (range * getUpperMargin());
                lower = lower - (long) (range * getLowerMargin());
            }

            upper = this.timeline.toMillisecond(upper);
            lower = this.timeline.toMillisecond(lower);
            DateRange dr = new DateRange(new Date(lower), new Date(upper));
            setRange(dr, false, false);
        }

    }

    /**
     * Selects an appropriate tick value for the axis.  The strategy is to
     * display as many ticks as possible (selected from an array of 'standard'
     * tick units) without the labels overlapping.
     *
     * @param g2  the graphics device.
     * @param dataArea  the area defined by the axes.
     * @param edge  the axis location.
     */
    protected void selectAutoTickUnit(Graphics2D g2, 
                                      Rectangle2D dataArea,
                                      RectangleEdge edge) {

        if (RectangleEdge.isTopOrBottom(edge)) {
            selectHorizontalAutoTickUnit(g2, dataArea, edge);
        }
        else if (RectangleEdge.isLeftOrRight(edge)) {
            selectVerticalAutoTickUnit(g2, dataArea, edge);
        }

    }

    /**
     * Selects an appropriate tick size for the axis.  The strategy is to
     * display as many ticks as possible (selected from a collection of 
     * 'standard' tick units) without the labels overlapping.
     *
     * @param g2  the graphics device.
     * @param dataArea  the area defined by the axes.
     * @param edge  the axis location.
     */
    protected void selectHorizontalAutoTickUnit(Graphics2D g2, 
                                                Rectangle2D dataArea, 
                                                RectangleEdge edge) {

        long shift = 0;
        if (this.timeline instanceof SegmentedTimeline) {
            shift = ((SegmentedTimeline) this.timeline).getStartTime();
        }
        double zero = valueToJava2D(shift + 0.0, dataArea, edge);
        double tickLabelWidth 
            = estimateMaximumTickLabelWidth(g2, getTickUnit());

        // start with the current tick unit...
        TickUnitSource tickUnits = getStandardTickUnits();
        TickUnit unit1 = tickUnits.getCeilingTickUnit(getTickUnit());
        double x1 = valueToJava2D(shift + unit1.getSize(), dataArea, edge);
        double unit1Width = Math.abs(x1 - zero);

        // then extrapolate...
        double guess = (tickLabelWidth / unit1Width) * unit1.getSize();
        DateTickUnit unit2 = (DateTickUnit) tickUnits.getCeilingTickUnit(guess);
        double x2 = valueToJava2D(shift + unit2.getSize(), dataArea, edge);
        double unit2Width = Math.abs(x2 - zero);
        tickLabelWidth = estimateMaximumTickLabelWidth(g2, unit2);
        if (tickLabelWidth > unit2Width) {
            unit2 = (DateTickUnit) tickUnits.getLargerTickUnit(unit2);
        }
        setTickUnit(unit2, false, false);
    }
    
    /**
     * Selects an appropriate tick size for the axis.  The strategy is to
     * display as many ticks as possible (selected from a collection of 
     * 'standard' tick units) without the labels overlapping.
     *
     * @param g2  the graphics device.
     * @param dataArea  the area in which the plot should be drawn.
     * @param edge  the axis location.
     */
    protected void selectVerticalAutoTickUnit(Graphics2D g2,
                                              Rectangle2D dataArea,
                                              RectangleEdge edge) {

        // start with the current tick unit...
        TickUnitSource tickUnits = getStandardTickUnits();
        double zero = valueToJava2D(0.0, dataArea, edge);

        // start with a unit that is at least 1/10th of the axis length
        double estimate1 = getRange().getLength() / 10.0;
        DateTickUnit candidate1 
            = (DateTickUnit) tickUnits.getCeilingTickUnit(estimate1);
        double labelHeight1 = estimateMaximumTickLabelHeight(g2, candidate1);
        double y1 = valueToJava2D(candidate1.getSize(), dataArea, edge);
        double candidate1UnitHeight = Math.abs(y1 - zero);

        // now extrapolate based on label height and unit height...
        double estimate2 
            = (labelHeight1 / candidate1UnitHeight) * candidate1.getSize();
        DateTickUnit candidate2 
            = (DateTickUnit) tickUnits.getCeilingTickUnit(estimate2);
        double labelHeight2 = estimateMaximumTickLabelHeight(g2, candidate2);
        double y2 = valueToJava2D(candidate2.getSize(), dataArea, edge);
        double unit2Height = Math.abs(y2 - zero);

       // make final selection...
       DateTickUnit finalUnit;
       if (labelHeight2 < unit2Height) {
           finalUnit = candidate2;
       }
       else {
           finalUnit = (DateTickUnit) tickUnits.getLargerTickUnit(candidate2);
       }
       setTickUnit(finalUnit, false, false);

    }

    /**
     * Estimates the maximum width of the tick labels, assuming the specified 
     * tick unit is used.
     * <P>
     * Rather than computing the string bounds of every tick on the axis, we
     * just look at two values: the lower bound and the upper bound for the 
     * axis.  These two values will usually be representative.
     *
     * @param g2  the graphics device.
     * @param unit  the tick unit to use for calculation.
     *
     * @return The estimated maximum width of the tick labels.
     */
    private double estimateMaximumTickLabelWidth(Graphics2D g2, 
                                                 DateTickUnit unit) {

        RectangleInsets tickLabelInsets = getTickLabelInsets();
        double result = tickLabelInsets.getLeft() + tickLabelInsets.getRight();

        Font tickLabelFont = getTickLabelFont();
        FontRenderContext frc = g2.getFontRenderContext();
        LineMetrics lm = tickLabelFont.getLineMetrics("ABCxyz", frc);
        if (isVerticalTickLabels()) {
            // all tick labels have the same width (equal to the height of 
            // the font)...
            result += lm.getHeight();
        }
        else {
            // look at lower and upper bounds...
            DateRange range = (DateRange) getRange();
            Date lower = range.getLowerDate();
            Date upper = range.getUpperDate();
            String lowerStr = null;
            String upperStr = null;
            DateFormat formatter = getDateFormatOverride();
            if (formatter != null) {
                lowerStr = formatter.format(lower);
                upperStr = formatter.format(upper);
            }
            else {
                lowerStr = unit.dateToString(lower);
                upperStr = unit.dateToString(upper);
            }
            FontMetrics fm = g2.getFontMetrics(tickLabelFont);
            double w1 = fm.stringWidth(lowerStr);
            double w2 = fm.stringWidth(upperStr);
            result += Math.max(w1, w2);
        }

        return result;

    }

    /**
     * Estimates the maximum width of the tick labels, assuming the specified 
     * tick unit is used.
     * <P>
     * Rather than computing the string bounds of every tick on the axis, we 
     * just look at two values: the lower bound and the upper bound for the 
     * axis.  These two values will usually be representative.
     *
     * @param g2  the graphics device.
     * @param unit  the tick unit to use for calculation.
     *
     * @return The estimated maximum width of the tick labels.
     */
    private double estimateMaximumTickLabelHeight(Graphics2D g2, 
                                                  DateTickUnit unit) {

        RectangleInsets tickLabelInsets = getTickLabelInsets();
        double result = tickLabelInsets.getTop() + tickLabelInsets.getBottom();

        Font tickLabelFont = getTickLabelFont();
        FontRenderContext frc = g2.getFontRenderContext();
        LineMetrics lm = tickLabelFont.getLineMetrics("ABCxyz", frc);
        if (!isVerticalTickLabels()) {
            // all tick labels have the same width (equal to the height of 
            // the font)...
            result += lm.getHeight();
        }
        else {
            // look at lower and upper bounds...
            DateRange range = (DateRange) getRange();
            Date lower = range.getLowerDate();
            Date upper = range.getUpperDate();
            String lowerStr = null;
            String upperStr = null;
            DateFormat formatter = getDateFormatOverride();
            if (formatter != null) {
                lowerStr = formatter.format(lower);
                upperStr = formatter.format(upper);
            }
            else {
                lowerStr = unit.dateToString(lower);
                upperStr = unit.dateToString(upper);
            }
            FontMetrics fm = g2.getFontMetrics(tickLabelFont);
            double w1 = fm.stringWidth(lowerStr);
            double w2 = fm.stringWidth(upperStr);
            result += Math.max(w1, w2);
        }

        return result;

    }

    /**
     * Calculates the positions of the tick labels for the axis, storing the 
     * results in the tick label list (ready for drawing).
     *