// CSE 331
// This file is posted as an example of Javadoc commenting.

/**
 * A Point object represents a 2-D (x, y) pair in the Cartesian plane.
 * @author Marty Stepp
 * @version 1.0
 */
public class Point implements Cloneable {
    private int x;                    // fields
    private int y;
    
    /**
     * Constructs a new point object at the origin, (0, 0).
     */
    public Point() {
        this(0, 0);
    }

    /**
     * Constructs a new point with the given x/y coordinates.
     * @param x the x-coordinate to use
     * @param y the x-coordinate to use
     */
    public Point(int x, int y) {      // constructor
        this.x = x;
        this.y = y;
    }
    
    /**
     * Creates a copy of this Point object.
     * @return the copy created
     */
    public Point clone() {
        try {
            // all of a Point's fields are primitive, so a shallow copy is fine
            Point copy = (Point) super.clone();
            return copy;
        } catch (CloneNotSupportedException e) {
            // won't happen
            return null;
        }
    }
    
    /**
     * Returns the direct distance between this point and the given other point.
     * @param p the point to measure against
     * @return the direct distance as a real number
     * @throws NullPointerException if p is null
     */
    public double distance(Point p) {
        int dx = x - p.x;
        int dy = y - p.y;
        return Math.sqrt(dx*dx + dy*dy);
    }
    
    /**
     * Returns whether o refers to a Point object with the same x/y
     * coordinates as this Point.
     * @param o the object to compare against
     * @return true if o refers to a Point object with the same x/y
     *         coordinates as this Point; otherwise false
     */
    public boolean equals(Object o) {
        if (o != null && getClass() == o.getClass()) {
            Point p = (Point) o;
            return p != null && x == p.x && y == p.y;
        } else {
            return false;
        }
    }

    /**
     * Returns the x-coordinate of this point.
     * @return the point's x-coordinate
     */
    public int getX() {
    	return x;
    }   // accessor
    
    /**
     * Returns the y-coordinate of this point.
     * @return the point's y-coordinate
     */
    public int getY() {
    	return y;
    }

    /**
     * Shifts the x/y position of this point by the given offsets.
     * @param dx the x-offset by which to shift
     * @param dy the y-offset by which to shift
     */
    public void translate(int dx, int dy) {
        x += dx;
        y += dy;
    }

    /**
     * Returns a string representation of this point, such as {@code "(3, -2)"}.
     */
    public String toString() {
        return "(" + x + ", " + y + ")";
    }
}