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Monday, 19 December 2016

Chapter 13 Exercise 9, Introduction to Java Programming, Tenth Edition Y. Daniel LiangY.

13.9 (Enable Circle comparable)
Rewrite the Circle class in Listing 13.2 to extend
GeometricObject and implement the Comparable interface.
Override the equals method in the Object class. Two Circle objects
are equal if their radii are the same. Draw the UML diagram that involves Circle,
GeometricObject, and Comparable.

import javafx.scene.shape.Rectangle;

public class MyRectangle2D extends GeometricObject {

    private static final int X = 0;
    private static final int Y = 1;

    public double centerX;
    public double centerY;

    public double width;
    public double height;

    public MyRectangle2D(double centerX, double centerY, double width, double height) {
        this.centerX = centerX;
        this.centerY = centerY;
        this.width = width;
        this.height = height;
    }

    public MyRectangle2D(MyPoint centerPoint, double width, double height) {
        this(centerPoint.x, centerPoint.y, width, height);
    }

    public MyRectangle2D(Rectangle rectangle) {
        this(rectangle.getX(), rectangle.getY(), rectangle.getWidth(), rectangle.getHeight());
    }

    public MyRectangle2D() {
        this(0, 0, 1, 1);
    }

    public MyPoint getCenterP() {
        return new MyPoint(centerX, centerY);
    }
    public MyPoint getP1() {
        return new MyPoint(centerX - width / 2, centerY + height / 2);
    }

    public MyPoint getP2() {
        return new MyPoint(centerX + width / 2, centerY + height / 2);
    }

    public MyPoint getP3() {
        return new MyPoint(centerX - width / 2, centerY - height / 2);
    }

    public MyPoint getP4() {
        return new MyPoint(centerX + width / 2, centerY - height / 2);
    }

    public double getCenterX() {
        return centerX;
    }

    public void setCenterX(double centerX) {
        this.centerX = centerX;
    }

    public double getCenterY() {
        return centerY;
    }

    public void setCenterY(double centerY) {
        this.centerY = centerY;
    }

    public double getWidth() {
        return width;
    }

    public void setWidth(double width) {
        this.width = width;
    }

    public double getHeight() {
        return height;
    }

    public void setHeight(double height) {
        this.height = height;
    }

    /** returns the perimeter of the rectangle. **/
    @Override
    public double getPerimeter() {

        return width * 2 + height * 2;
    }

    /** returns the area of the rectangle **/
    @Override
    public double getArea() {
        return width * height;
    }

    public boolean contains(double x, double y) {

        // Get max X & Y
        double maxX = getMax(getP1().x, getP2().x, getP3().x, getP4().x);
        double maxY = getMax(getP1().y, getP2().y, getP3().y, getP4().y);
        // Get min X & Y
        double minX = getMin(getP1().x, getP2().x, getP3().x, getP4().x);
        double minY = getMin(getP1().y, getP2().y, getP3().y, getP4().y);

        if (x < minX || x > maxX || y < minY || y > maxY)  return false;

        return true;

    }

    public boolean contains(MyRectangle2D r2) {
        double xDistance = (r2.centerX > centerX) ? r2.centerX - centerX : centerX - r2.centerX;
        double yDistance = (r2.centerY > centerY) ? r2.centerY - centerY : centerY - r2.centerY;

        // if the r2 is inside this rectangle
        // this is only valid if the rectangles are parallel
        return (xDistance <= (width - r2.width) / 2 && yDistance <= (height - r2.height) / 2);

    }

    public boolean overlaps(MyRectangle2D r2) {
        // subtract from the highest number
        double xDistance = (r2.centerX > centerX) ? r2.centerX - centerX : centerX - r2.centerX;
        double yDistance = (r2.centerY > centerY) ? r2.centerY - centerY : centerY - r2.centerY;

        // if the r2 overlaps this rectangle
        // this is only valid if the rectangles are parallel
        return (xDistance <= (width + r2.width) / 2 && yDistance <= (height + r2.height) / 2);

    }

    public static boolean r1OverLapsR2(Rectangle r1, Rectangle r2) {
        return r1.intersects(r2.getBoundsInLocal()) || r2.intersects(r1.getBoundsInLocal());
    }

    public javafx.scene.shape.Rectangle getRectangle() {
        return new Rectangle(centerX, centerY, width, height);
    }
    public boolean contains(MyPoint[] points) {

        for (MyPoint p : points) {
            if (!contains(p)) return false;
        }
        return true;
    }

    public boolean contains(MyPoint point) {
        return contains(point.x, point.y);
    }

    public static MyRectangle2D getRectangle(double[][] points) {

        // find leftLowestPoint

        // find rightMostPoint

        // find the center from highest and lowest point

        // x distance = width

        // y distance = height
        MyPoint[] myPoints = new MyPoint[points.length];
        for (int i = 0; i < points.length; i++) {
            myPoints[i] = new MyPoint(points[i][0], points[i][1]);
        }

        return getRectangle(myPoints);
    }

    public static MyRectangle2D getRectangle(MyPoint[] points) {

        MyPoint leftMost = getLeftMostPoint(points);
        MyPoint rightMost = getRighMostPoint(points);
        double width = Math.abs(rightMost.x - leftMost.x);

        MyPoint highest = getHighestPoint(points);
        MyPoint lowest = getLowestPoint(points);
        double height = Math.abs(highest.y - lowest.y);

        double centerX = highest.getCenterPoint(lowest).x;
        double centerY = leftMost.getCenterPoint(rightMost).y;

        return new MyRectangle2D(centerX, centerY, width, height);
    }

    private static MyPoint getLeftMostPoint(MyPoint[] points) {

        MyPoint leftMost = points[0];
        for (int i = 0; i < points.length; i++) {
            if (leftMost.x > points[i].x) {
                leftMost = points[i];
            }
        }
        return leftMost;
    }

    private static MyPoint getRighMostPoint(MyPoint[] points) {

        MyPoint rightMost = points[0];
        for (int i = 0; i < points.length; i++) {
            if (rightMost.x < points[i].x) {
                rightMost = points[i];
            }
        }
        return rightMost;
    }

    private static MyPoint getHighestPoint(MyPoint[] points) {

        MyPoint highest = points[0];
        for (int i = 0; i < points.length; i++) {
            if (highest.y < points[i].y) {
                highest = points[i];
            }
        }
        return highest;
    }

    private static MyPoint getLowestPoint(MyPoint[] points) {

        MyPoint lowest = points[0];
        for (int i = 0; i < points.length; i++) {
            if (lowest.y > points[i].y) {
                lowest = points[i];
            }
        }
        return lowest;
    }

    private double getMax(double... n) {
        double max = n[0];
        for (int i = 1; i < n.length; i++) {
            if (max < n[i]) {
                max = n[i];
            }
        }
        return max;
    }
    private double getMin(double... n) {
        double min = n[0];
        for (int i = 1; i < n.length; i++) {
            if (min > n[i]) {
                min = n[i];
            }
        }
        return min;
    }

    @Override
    public String toString() {
        return "MyRectangle2D{" +
                "centerX=" + centerX +
                ", centerY=" + centerY +
                ", width=" + width +
                ", height=" + height +
                '}';
    }
}

public abstract class GeometricObject implements Comparable<GeometricObject> {
    private String color = "white";
    private boolean filled;
    private java.util.Date dateCreated;

    /** Construct a default geometric object */
    protected GeometricObject() {
        dateCreated = new java.util.Date();
    }

    /** Construct a geometric object with color and filled value */
    protected GeometricObject(String color, boolean filled) {
        dateCreated = new java.util.Date();
        this.color = color;
        this.filled = filled;
    }

    /** Return color */
    public String getColor() {
        return color;
    }

    /** Set a new color */
    public void setColor(String color) {
        this.color = color;
    }

    /** Return filled. Since filled is boolean,
     *  the get method is named isFilled */
    public boolean isFilled() {
        return filled;
    }

    /** Set a new filled */
    public void setFilled(boolean filled) {
        this.filled = filled;
    }

    /** Get dateCreated */
    public java.util.Date getDateCreated() {
        return dateCreated;
    }

    /** Return a string representation of this object */
    @Override
    public String toString() {
        return "created on " + dateCreated + "\ncolor: " + color +
                " and filled: " + filled;
    }

    @Override
    public int compareTo(GeometricObject o) {
        if (getArea() > o.getArea())
            return 1;
        else if (getArea() < o.getArea())
            return -1;
        else
            return 0;
    }

    public static GeometricObject max(GeometricObject o1, GeometricObject o2) {
        return (o1.compareTo(o2) >= 0) ? o1 : o2;
    }

    public static double sumArea(GeometricObject[] a) {
        double sum = 0;
        for (GeometricObject o : a) {
            sum += o.getArea();
        }
        return sum;
    }
    /** Abstract method getArea */
    public abstract double getArea();

    /** Abstract method getPerimeter */
    public abstract double getPerimeter();
}

public class Exercise_09 {

    public static void main(String[] args) {

        Circle c1 = new Circle(10);
        Circle c2 = new Circle(10);
        MyRectangle2D r1 = new MyRectangle2D(0, 0, 5, 5);

        System.out.println("c1 equals c2? " + c1.equals(c2));
        System.out.println("c1 equals r1? " + c1.equals(r1));
    }
}

class Circle extends GeometricObject {
    private double radius;

    public Circle() {
    }

    public Circle(double radius) {
        this.radius = radius;
    }

    public Circle(double radius,
                  String color, boolean filled) {
        this.radius = radius;
        setColor(color);
        setFilled(filled);
    }

    /** Return radius */
    public double getRadius() {
        return radius;
    }

    /** Set a new radius */
    public void setRadius(double radius) {
        this.radius = radius;
    }

    /** Return area */
    public double getArea() {
        return radius * radius * Math.PI;
    }

    /** Return diameter */
    public double getDiameter() {
        return 2 * radius;
    }

    /** Return perimeter */
    public double getPerimeter() {
        return 2 * radius * Math.PI;
    }

    @Override
    public boolean equals(Object obj) {
        return obj instanceof Circle && radius == ((Circle) obj).radius;
    }

    /* Print the circle info */
    public void printCircle() {
        System.out.println("The circle is created " + getDateCreated() +
                " and the radius is " + radius);
    }
}

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