Setting the constraint twice before calling add()

Question

I am learning GridBagLayout in swing using tutorials form Oracle.
As we all know, we can set the constraint again after being used by 1 component.Here I noticed the author is set the constraint again before call the method add().

public class GridBagLayoutDemo {
//Here I have no idea why these 3 lines for
    final static boolean shouldFill = true;
    final static boolean shouldWeightX = true;
    final static boolean RIGHT_TO_LEFT = false;

    public static void addComponentsToPane(Container pane) {
//1)why not just ignore the above declaration and just type 
//pane.setComponentOrientation(ComponentOrientation.RIGHT_TO_LEFT); ?

        if (RIGHT_TO_LEFT) {
            pane.setComponentOrientation(ComponentOrientation.RIGHT_TO_LEFT);
        }

        JButton button;
    pane.setLayout(new GridBagLayout());
    GridBagConstraints c = new GridBagConstraints();
//same go to here
    if (shouldFill) {
    //natural height, maximum width
    c.fill = GridBagConstraints.HORIZONTAL;
    }
//2)the author set the constraint in above line,then author set it again in below line
    button = new JButton("Button 1");
    if (shouldWeightX) {
    c.weightx = 0.5;
    }
//here it is
    c.fill = GridBagConstraints.HORIZONTAL;
    c.gridx = 0;
    c.gridy = 0;
    pane.add(button, c);

Anyone please answer both my questions?

Answer 1

I think that the second layout orientation: c.fill = GridBagConstraints.HORIZONTAL; is a mistake, the first one is conditional and depends from the previous seted value "shouldFill". So I do not agree that this variable does nothing.