CategoryPlot plotBar = chart.getCategoryPlot();
NumberAxis na= (NumberAxis)plotBar.getRangeAxis();
na.setStandardTickUnits(NumberAxis.createIntegerTickUnits());
CategoryPlot plotBar = chart.getCategoryPlot();
NumberAxis na= (NumberAxis)plotBar.getRangeAxis();
na.setStandardTickUnits(NumberAxis.createIntegerTickUnits());