title: Jfreechart - Refresh a chart according to changing data
body: <p>I would like to know how to refresh a chart if we want to change "in live" some piece of data. I mean for instance, I have a chart with a TaskSeries which appears on 3 years and I would like to change 3 years by 5 years. I want the chart to change immediately.</p>
  
  <p>Is there some kind of update chart or something like that ?</p>
  
  <p>I know that you could say "get your TaskSeries, do your changes and it will be refreshed automatically" but my TaskSeries are generated and I cannot easily change these ones. That's why I would like to find a way to recalculate and to rebuild the whole chart.</p>