TickUnits use wrong hours

[Qohelet]

Hello!

I'm using jFreeChart 1.0.13 and I want to set a TickUnit every six hours. At 6, 12, 18 and 24:00. For this I used the following Code:

Code: Select all

((DateAxis) plot.getDomainAxis()).setTickUnit(new DateTickUnit(DateTickUnitType.HOUR,6, new SimpleDateFormat("EE dd.MM HH")));
((DateAxis) plot.getDomainAxis()).setTickMarkPosition(DateTickMarkPosition.START);

And it was possible to create this Chart with my Test-Data - the TickUnits are all on the right place:


So I copied the Java-Classes in a JSP-Webproject to work with the real data. Now the Units are placed on 5, 11, 17 and 23:00:


How can I fix this Problem? Thanks for your help!

[david.gilbert]

I'm a little puzzled, because the DateAxis class doesn't support rotated labels, but you have them in the sample charts.

My guess would be that a time zone difference is affecting your chart, but I don't know if that is in the dataset, the axis, or the DateFormatter you are using.

[Qohelet]

It's not very difficult to do this - DateAxis has to be changed a little bit:

1. I need two new variables

Code: Select all

private double winkel;                      //The angle I need
private boolean mywinkel = false;     //Do I need the angle?

2. Then I need getter/setter:

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    public double getWinkel() {
        return winkel;
    }

    public void setWinkel(double winkel) {
        this.mywinkel = true;
        this.winkel = Math.toRadians(winkel);
    }

    public boolean isMywinkel() {
        return mywinkel;
    }

3. And then I change the refreshTicksHorizontal-Method at the if-Statements:

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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;
                    }
                } 
                if (isMywinkel()) {
                    System.out.println("meiwinkl");
                    anchor = TextAnchor.CENTER_RIGHT;
                    rotationAnchor = TextAnchor.CENTER_RIGHT;
                    if (edge == RectangleEdge.TOP) {
                        angle = getWinkel();
                    } else {
                        angle = -getWinkel();
                    }
                }
                else {
                    if (edge == RectangleEdge.TOP) {
                        anchor = TextAnchor.BOTTOM_CENTER;
                        rotationAnchor = TextAnchor.BOTTOM_CENTER;
                    } else {
                        anchor = TextAnchor.TOP_CENTER;
                        rotationAnchor = TextAnchor.TOP_CENTER;
                    }
                }

4. And the refreshTicksVertical-Method also at the Statements:

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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;
                    }
                }                
                if (isMywinkel()) {
                    System.out.println("meiwinkl");
                    anchor = TextAnchor.BOTTOM_CENTER;
                    rotationAnchor = TextAnchor.BOTTOM_CENTER;
                    if (edge == RectangleEdge.LEFT) {
                        angle = -this.winkel;
                    } else {
                        angle = this.winkel;
                    }
                }
                else {
                    if (edge == RectangleEdge.LEFT) {
                        anchor = TextAnchor.CENTER_RIGHT;
                        rotationAnchor = TextAnchor.CENTER_RIGHT;
                    } else {
                        anchor = TextAnchor.CENTER_LEFT;
                        rotationAnchor = TextAnchor.CENTER_LEFT;
                    }
                }

5. And in my program it looks like this:

Code: Select all

((DateAxis) plot.getDomainAxis()).setVerticalTickLabels(true);
((DateAxis) plot.getDomainAxis()).setWinkel(47.9);
chart.getLegend().setPosition(RectangleEdge.RIGHT);

[Qohelet]

But back to my question... No - I don't think that the TimeZone is the problem because the old project works correctly and my location hasn't changed - or do you mean something particular?

Here are the important parts of my Program:

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this.chart = ChartFactory.createCandlestickChart(
                    this.mainTitle,
                    this.getDaname(),
                    this.getRaname(),
                    this.getDhld(),    /* A defaultHighLowDataset*/
                    true);

        XYPlot plot = chart.getXYPlot();

        plot.setDatasetRenderingOrder(DatasetRenderingOrder.FORWARD);
        DateAxis dax = (DateAxis) plot.getDomainAxis();

        dax.setTickMarkPosition(DateTickMarkPosition.MIDDLE);

        ValueAxis axis = new NumberAxis(this.getRaname());
        plot.setRangeAxisLocation(i, AxisLocation.BOTTOM_OR_LEFT);

        ((DateAxis) plot.getDomainAxis()).setTickUnit(getTickunit());
        ((DateAxis) plot.getDomainAxis()).setTickMarkPosition(DateTickMarkPosition.START);

        ((DateAxis) plot.getDomainAxis()).setVerticalTickLabels(true);
        ((DateAxis) plot.getDomainAxis()).setWinkel(getAngle());
        chart.getLegend().setPosition(RectangleEdge.RIGHT);

                DateAxis das = (DateAxis) plot.getDomainAxis();
                Date lower = das.getMinimumDate();
                Date higher = das.getMaximumDate();

                long millis = lower.getTime();


                do {
                    final Marker originalEnd = new ValueMarker(millis);

                    originalEnd.setPaint(Color.BLACK);
                    originalEnd.setStroke(new BasicStroke((float) 1.5));
                    plot.addDomainMarker(originalEnd);

                    RegularTimePeriod myrtp = RegularTimePeriod.createInstance(this.rtp.getClass(), new Date(millis), TimeZone.getDefault());
                    myrtp = myrtp.next();
                    millis = myrtp.getFirstMillisecond();

                } while (millis <= higher.getTime());

That's it... Do you have any ideas...?

edit: Another reason why I don't think that the problem is the timezone: All values are displayed correct - just moved

[Qohelet]

No idea...?

Could it be a bug?

[keshava]

Hi,

Can We use the above mentioned code to display labels at an angle.. The official Jfreechart library doesn't support it, and I'm wondering there must be a reason not to do it . They would have incorporated it if it would have been a simple fix..

@ Gilbert ,
Any inputs whether we can use that ??

[jleech]

David, Keshava
Here is my version of rotated labels, which also sets the height properly. (replace Math.PI / -4.0 with your favorite angle in radians) Biggest issue I see with incorporating it into JFreechart codebase would be that if the labels are long enough, and the Y-axis not wide enough, the left edge of the label text can be clipped off the chart. The code would have to calculate the room necessary for the label, and if there isn't room, would have to adjust the left padding as necessary.
-Jonathan

Code: Select all

final DateAxis axis = new DateAxis(xAxisLabel) {
               @SuppressWarnings("unchecked")
               @Override
               protected List refreshTicksHorizontal(Graphics2D g2, Rectangle2D dataArea, RectangleEdge edge) {
                  List ticks = super.refreshTicksHorizontal(g2, dataArea, edge);
                  List ret = new ArrayList();
                  for (Tick tick : (List<Tick>)ticks) {
                     if (tick instanceof DateTick) {
                        DateTick dateTick = (DateTick)tick;
                        ret.add(new DateTick(dateTick.getDate(), dateTick.getText(), dateTick.getTextAnchor(), dateTick.getRotationAnchor(), Math.PI / -4.0));
                     } else {
                        ret.add(tick);
                     }
                  }
                  return ret;
               }
               protected double findMaximumTickLabelHeight(java.util.List ticks, java.awt.Graphics2D g2, java.awt.geom.Rectangle2D drawArea, boolean vertical) {
                  return super.findMaximumTickLabelHeight(ticks, g2, drawArea, vertical) * Math.sin(Math.PI / 4.0);
               }
};
axis.setVerticalTickLabels(true);
plot.setDomainAxis(axis);