point.java

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/**
 * This class models a point in the Cartesian plane.
 *
 * @author author name
 * @version 1.0.0
 */
public class Point  {

    /* Number of instances created */
    private static int numberOfInstances = 0;

    /* x coordinate of this point*/
    private int  x;

    /* y coordinate of this point*/
    private int  y;

    /**
     * Test driver for class <code>Point</code>.
     *
     * @param args  not used
     */
    public static void main(String[] args) {

        Point pointOne = new Point(10, 100);

        System.out.println("x: " + pointOne.getX());
        System.out.println("y: " + pointOne.getY());

        pointOne.setX(20);
        pointOne.setY(200);

        System.out.println("new x: " + pointOne.getX());
        System.out.println("new y: " + pointOne.getY());

        System.out.println("Instances before PointTwo is created: " +
                           Point.getNumberOfInstances());

        Point pointTwo = new Point(20, 200);

        System.out.println("Instances after PointTwo is created: " +
                           Point.getNumberOfInstances());
    }

    /**
     * Creates a <code>Point</code> object and increments the
     * number of instances.
     *
     * @param initialX  the x coordinate
     * @param initialY  the y coordinate
     */
    public Point(int  initialX, int  initialY)  {

        x = initialX;
        y = initialY;

        numberOfInstances++;
    }

    /**
     * Returns the number of <code>Point</code> instances that
     * have been created.
     *
     * @return the number of <code>Point</code> instances that
     *         have been created.
     */
    public static int  getNumberOfInstances()  {

        return numberOfInstances;
    }

    /**
     * Returns the x coordinate of this point.
     *
     * @return the x coordinate of this point.
     */
    public int  getX()  {

        return x;
    }

    /**
     * Returns the y coordinate of this point.
     *
     * @return the y coordinate of this point.
     */
    public int  getY()  {

        return y;
    }

    /**
     * Modifies the x coordinate of this point.
     *
     * @param newX  the new x coordinate
     */
    public void  setX(int  newX)  {

        x = newX;
    }

    /**
     * Modifies the y coordinate of this point.
     *
     * @param newY  the new y coordinate
     */
    public void  setY(int  newY)  {

        y = newY;
    }
    
    /**
     * Overrides {@link Object#equals(Object)}.
     * <p>
     * Two <code>Point</code> objects are equal if their x and y
     * coordinates are the same.
     * </p>
     *
     * @param object  object which this <code>Point</code> is
     *                compared.
     * @return  <code>true</code> if the x and y coordinates of
     *          this <code>Point</code> are equal to the x and y
     *          coordinates of the argument; <code>false</code>
     *          otherwise.
     */
//    public boolean  equals(Object  object)  {
//
//        if (object instanceof Point) {
//
//            Point point = (Point) object;
//
//            return point.getX() == getX() && point.getY() == getY();
//
//        } else {
//
//            return false;
//        }
//    }

    /**
     * Overrides {@link Object#toString()}.
     * <p>
     * Returns a string representation of this <code>Point</code>
     * object.
     * </p>
     *
     * @return  a string representation of this <code>Point</code>
     *          object.
     */
//    public String toString() {
//
//        return "(" + getX() + "," + getY() + ")";
//    }
}