vg.setGridColor("#000000");
TimeGeometry tg = new DefaultTimeGeometry();
tg.setGridStep(2 * 60 * 60 * 1000);
tg.setAxisLabelsPlacement("bottom");
tg.setGridStepRange(30 * 60 * 1000);
PlotDataSource pds = new PlotDataSource();
pds.setSeparator(" ");
dfPlot1.setPlotDataSource(pds);
dfPlot1.setValueGeometry(vg);
dfPlot1.setTimeGeometry(tg);
dfPlot1.setDataModel(dataModel1);
dfPlot2.setPlotDataSource(pds);