// A very simple class that defines a cartesian point, and has a translate
// method, a constructor, and a toString() method.  Enforces that the
// point is never negative.

public class Point {
    private int x;    // an "instance variable" defining the point's x value
    private int y;    // an "instance variable" defining the point's y value

    // a constructor method for a Point object
    public Point(int x, int y) {
        if (x < 0 || y < 0) {
            throw new IllegalArgumentException("components shouldn't be -ve");
        }
        this.x = x;
        this.y = y;
    }

    // returns X coordinate
    public int getX() {
        return this.x;
    }

    // returns Y coordinate
    public int getY() {
        return this.y;
    }

    // sets coordinates
    public void setLocation(int x, int y) {
        if (x < 0 || y < 0) {
            throw new IllegalArgumentException();
        }
        this.x = x;
        this.y = y;
    }

    // this method translates the point by (dx, dy)
    public void translate(int dx, int dy) {
        if ( (this.x + dx < 0) || (this.y + dy < 0)) {
            throw new IllegalArgumentException("components shouldn't be -ve");
        }

        this.x += dx;   // "this" is a reference to the object instance
        this.y += dy;   // whose translate method was invoked
    }

    // a more useful toString() method to print the Point's value
    public String toString() {
        return "(" + this.x + ", " + this.y + ")";
    }
    // implement an equals that compares the coordinates
    public boolean equals(Point p) {
		return x == p.x && y == p.y;
	}
}