public void paintIcon(Component c, Graphics g, int x, int y) {
Color color = c == null ? Color.GRAY : c.getBackground();
// In a compound sort, make each succesive triangle 20%
// smaller than the previous one.
int dx = (int) (size / 2 * Math.pow(0.8, priority));
int dy = descending ? dx : -dx;
// Align icon (roughly) with font baseline.
y = y + 5 * size / 6 + (descending ? -dy : 0);
int shift = descending ? 1 : -1;
g.translate(x, y);
// Right diagonal.
g.setColor(color.darker());
g.drawLine(dx / 2, dy, 0, 0);
g.drawLine(dx / 2, dy + shift, 0, shift);
// Left diagonal.
g.setColor(color.brighter());
g.drawLine(dx / 2, dy, dx, 0);
g.drawLine(dx / 2, dy + shift, dx, shift);
// Horizontal line.
if (descending) {
g.setColor(color.darker().darker());
} else {
g.setColor(color.brighter().brighter());
}
g.drawLine(dx, 0, 0, 0);
g.setColor(color);
g.translate(-x, -y);
}
// Overridden for performance reasons. ---->
@Override
public boolean isOpaque() {
Color back = getBackground();
Component p = getParent();
if (Objects.nonNull(p)) {
p = p.getParent();
} // p should now be the JTable.
boolean colorMatch =
Objects.nonNull(back)
&& Objects.nonNull(p)
&& back.equals(p.getBackground())
&& p.isOpaque();
return !colorMatch && super.isOpaque();
}