Setting Initial Value In JFreeChart

[Tanzy Akhtar]

Hi,

The program is creating time chart using

 ChartFactory.createTimeSeriesChart(.....)   

In the program, take the current sysdate. Now chart should start with one hour back date form current sysdate,
And it must be of ten minutes of interval.
How to achieve this?


Thansk,
Tanzy.

[Ulf Dittmer]

Lots of JFreeChart TimeSeries demos can be found at http://www.java2s.com/Code/Java/Chart/Time-Series-Chart.htm

[Tanzy Akhtar]

Thank you Ulf for the reply.
Well i used this for the the demonstration.

In this example, what i saw that x axis value is not fixed. Its getting changed as per value of minute given in data.
For example --

1. Use the sample program with nothing changed.
X axis --> 20:02, 20:04,20:06.......

2. commented these four value --

   series.add(new Minute(9, hour), 14.6);
        series.add(new Minute(11, hour), 11.9);
        series.add(new Minute(15, hour), 13.5);
        series.add(new Minute(19, hour), 10.9);   

x axis value --> 21:01:00, 21:01:30, 21:02:00,....

And so on.
I am not getting, how to control these value?

[Ulf Dittmer]

The way to alter the display of axis values is: JFreeChart.getPlot --> Plot --> cast to XYPlot --> getDomainAxis --> valueAxis --> cast to DateAxis --> setDateFormatOverride(DateFormat). Check the javadocs of those classes for details.

[Tanzy Akhtar]

Thank you Ulf.
I added this to above piece of code

   
XYPlot plot = chart.getXYPlot();
DateAxis valueAxis = (DateAxis) plot.getDomainAxis();
valueAxis.setDateFormatOverride(new SimpleDateFormat("hh:mm"));

Now the formatting is under control. But still the core problem is not fulfilled, i.e. how to start the x-axis value with one hour back time from the current time. For example if current time is 11:30 PM, the xaxis should start with 10:30 PM.

[Ulf Dittmer]

That's just a matter of passing the correct data to JFC. Which values *are* you passing to it? What prevents you from passing the correct values?