public class Point
{
    private final int x;
    private final int y;  //final means "cannot be reassigned"
    public Point(int x, int y)   // sig is [int, int]
    {
        this.x = x;
        this.y = y;
    }
    public Point()   // sig is []
    {
        //x = 0;
        //y = 0;
        this(0,0);  //calls sibling constructor
    }
    /*
     * method name overloading
     * several methods can have the same name if their
     * sigs are different.
     *
     * You should only use this for closely related methods.
     */
    public double distanceTo(Point other)
    {
        return Math.hypot(x - other.x, y - other.y);
    }
    @Override
    public String toString()
    {
        return String.format("(%s, %s)", x, y);
    }
    @Override 
    public boolean equals(Object o)
    {
        if(this == o)
        {
            return true;
        }
        if(!(o instanceof Point))
        {
            return false;
        }
        //o must be a Point!
        Point that = (Point) o;
        return x == that.x && y == that.y;
    }
    public Point reflectionAcrossX()
    {
        return new Point(x, -y);
    }
    public Point reflectionAcrossY()
    {
        return new Point(-x, y);
    }
    public Point reflectionAcrossYequalsX()
    {
        return new Point(y, x);
    }
    public int getX()
    {
        return x;
    }
    public int getY()
    {
        return y;
    }
    public static void main(String[] args)
    {
        Point p = new Point(3,4);
        Point q = new Point(0,0);
        System.out.println(p.x);
        System.out.println(p.y);
        System.out.println(p.distanceTo(q));
        System.out.println(p);
        System.out.println(p.reflectAcrossX());
    }
}