How to set different colors to the bars in stacked bar chart in ireport?

I need to set a unique color to each bar in the stacked bar chart. Whatever the color I see in one bar it shouldn't be repeated in any other bar or any other stack.

For example: I have 5 bars in the report. Each bar has 3 different stacks. I want to apply a red related colors to the first bar and it开发者_如何学Cs stacks. Second bar should have blue related colors. etc.. It is showed in the attached image. The image shows a very basic requirement what we want. Just created using a normal ms paint. Stacked Bar MS Paint Image

You can override the getItemPaint() method of StackedBarRenderer() to return the desired color. You can use getHSBColor() to construct related colors by varying the brightness or saturation for a given hue.

Addendum: The example below will print out the row, column and color for each item. You can use the result as a guide to which custom color you want to return. See BarChartDemo1 for a sample dataset.

plot.setRenderer(new MySBRenderer());
...
private static class MySBRenderer extends StackedBarRenderer {

    @Override
    public Paint getItemPaint(int row, int col) {
        System.out.println(row + " " + col + " " + super.getItemPaint(row, col));
        return super.getItemPaint(row, col);
    }
}