To update the chart's style without recreating the style object you need to change the chart's styles and then call repaint() method to refresh the chart. For example, to rotate a pie chart by 5 degrees you can use the following code:

	MxPieChartStyle style = (MxPieChartStyle) chart.getStyle();
	style.angle += 5; 
	chart.repaint();

You can see this example running by selecting Samples topic of Swing section in WebCharts3D Designer's Help and clicking the appropriate sample link.