JFreechart SeriesException

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 02:00:0开发者_Go百科1";
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);
}

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.

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);

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);