// gca.getStart().getColor().setRed(ColorUtil.getRedFromHex(colorStart));
gca.getStart().setLocationType(locationTypeStart);
gca.getStart().setLocationValue(locationValueStart);
gca.setEnd(StylesFactory.eINSTANCE.createGradientColoredLocation());
final Color endColor = gaService.manageColor(diagram, ColorUtil.getRedFromHex(colorEnd)
, ColorUtil.getGreenFromHex(colorEnd)
, ColorUtil.getBlueFromHex(colorEnd));
gca.getEnd().setColor(endColor);
gca.getEnd().setLocationType(locationTypeEnd);