public class Vector2D private double private double public double getX

public class Vector2D {
    private double x;
    private double y;

    public double getX() {
        return x;
    }

    public void setX(double x) {
        this.x = x;
    }

    public double getY() {
        return y;
    }

    public void setY(double y) {
        this.y = y;
    }

    public Vector2D() {
        this(0,0);
    }
    public Vector2D (double x, double y) {
        this.x = x;
        this.y = y;
    }
    public Vector2D add (Vector2D) {
        return new Vector2D
    }
}