tf.setBorder(new LineBorder(Color.red,1));
//new LineBorder(color,width);
Because the method is overloaded you can define the Color, and leave the rest to the default.
Alternatively, you can define the whole method and choose the Color, line Thickness, and type of corners; rounded or not.
public LineBorder(Color color) {
this(color, 1, false);
}
public LineBorder(Color color, int thickness) {
this(color, thickness, false);
}
@ConstructorProperties({"lineColor", "thickness", "roundedCorners"})
public LineBorder(Color color, int thickness, boolean roundedCorners) {
lineColor = color;
this.thickness = thickness;
this.roundedCorners = roundedCorners;
}