JFreechart SeriesException

问题:

I am trying to plot a bar chart using timeseries by introducing the beginning and the end date , but i got a problem with the end date it indicate : Exception in thread "main" org.jfree.data.general.SeriesException: You are attempting to add an observation for the time period 4-mai-2011 but the series already contains an observation for that time period. Duplicates are not permitted. Try using the addOrUpdate() method.

final TimeSeries series2 = new TimeSeries("ip max", Day.class);  String datebegin = "04/29/2011 02:00:01"; String dateend = "05/04/2011 02:00:01"; DateFormat formatter; Date date; formatter = new SimpleDateFormat("MM/dd/yyyy HH:mm:ss"); date = formatter.parse(datebegin); Calendar cal1 = Calendar.getInstance(); cal1.setTime(date); Date date2; date2 = (Date) formatter.parse(dateend); Calendar cal2 = Calendar.getInstance(); cal2.setTime(date2); while (((cal1.compareTo(cal2)) != 0))  {     cal1.add(Calendar.HOUR, 24);     String intermediatestringdate = formatter.format(cal1.getTime());     System.out.println( intermediatestringdate);     Date intermediatedate = (Date) formatter.parse(dateend);     series2.add(new Day(intermediatedate),500); } 

回答1:

Assuming you are creating a time-based bar chart using ChartFactory.createXYBarChart() with an IntervalXYDataset, just construct the domain of your TimeSeries with a suitable TimePeriod.

private static IntervalXYDataset createDataset() {     TimeSeries series = new TimeSeries("Series");     RegularTimePeriod day = new Day(29, 4, 2011);     RegularTimePeriod end = new Day(4, 5, 2011);     int i = 1;     while (day.compareTo(end) < 1) {         series.addOrUpdate(day, i++);         day = day.next();     }     TimeSeriesCollection dataset = new TimeSeriesCollection();     dataset.addSeries(series);     return dataset; } 

Also, note that Day.class is no longer required by TimeSeries.

回答2:

If you change the TimeSeries and TimeSeriesCollection to be TimePeriodValues and TimePeriodValuesCollection, you will not have the unique time constraint to deal with.

here's what i did, and i'm able to plot time values along the x-axis that are identical down to the millisecond:

    TimePeriodValues data = new TimePeriodValues("duration");      for(int x=0; x<_stats.getDataPoints().size();x++)     {         DataPoint dp = _stats.getDataPoints().get(x);          data.add(new Millisecond(dp._date),dp._duration);      }     TimePeriodValuesCollection dataset = new TimePeriodValuesCollection();       dataset.addSeries(data);      JFreeChart chart = ChartFactory.createScatterPlot("Title", "start time", "duration (millis)", dataset, PlotOrientation.VERTICAL, true, true, false);     XYPlot plot = chart.getXYPlot();     plot.setDomainAxis(new DateAxis());      DateAxis domainAxis = (DateAxis)plot.getDomainAxis();      domainAxis.setDateFormatOverride(new SimpleDateFormat("yyyy/MM/dd HH:mm:ss.SSS"));      ChartUtilities.saveChartAsPNG(new File(_reportFolder+File.separator+uuid+".png"), chart, 500, 300); 

回答3:

I believe here is the root cause of the problem. When adding list of time/value in the TimeSeries, the time point added must be unique from the whole list.
series2.add(new Day(intermediatedate),500);

Otherwise, using addOrUpdate if there are possibilities of the time in the list.
series2.addOrUpdate(new Day(intermediatedate),500);

文章来源: JFreechart SeriesException