//operating system linux,ubuntu,Mac /*********************GeometricObject.java**********************/ public abstract class GeometricObject { private String color = \"white\"; private boolean filled; // default constructure public GeometricObject() { super(); // TODO Auto-generated constructor stub } // construct a Geometric Object // parameterized constructure public GeometricObject(String color, boolean filled) { this.color = color; this.filled = filled; } /** Getter method for color */ public String getColor() { return color; } /** Setter method for color */ public void setColor(String color) { this.color = color; } /** * Getter method for filled. Since filled is boolean, so the gret method * name is isFilled */ public boolean isFilled() { return filled; } /** Setter method for filled */ public void setFilled(boolean filled) { this.filled = filled; } /** Abstract method for FindArea */ public abstract double findArea(); /** Abstract method for findPerimeter */ public abstract double findPerimeter(); } /*****************************Octagon.java**************/ public class Octagon extends GeometricObject implements Cloneable, Comparable { private double side; /** construct a Octagon with specified side */ public Octagon(double side) { super(); this.side = side; } /** Implement the abstract method findArea in GeometricObject */ @Override public double findArea() { double area = (2 + 4 / Math.sqrt(2)) * side * side; return area; } /** Implement the abstract method findArea in findPerimeter */ @Override public double findPerimeter() { double perimeter = 8 * side; return perimeter; } /** Implement the compareTo method in Comparable interface */ @Override public int compareTo(Object o) { // TODO Auto-generated method stub return 0; } public Object clone() throws CloneNotSupportedException { return super.clone(); } } /*******************App.java*******************/ public class App { public static void main(String[] args) { Octagon a1 = new Octagon(5);//creating object of octagon System.out.println(\"Area of a1 is \" + a1.findArea()); System.out.println(\"Perimeter of a1 is \" + a1.findPerimeter()); Object a2; try { a2 = a1.clone(); String result = (a1.compareTo(a2) == 0) ? \"a1 and its clone a2 have the same area\" : \"a1 and its clone a2 have different areas\"; System.out.println(\"Compare a1 and its clone a2:\ \\t \" + result); System.out.println(\"Hashcode of a1: \" + a1.hashCode()); System.out.println(\"Hashcode of a2: \" + a2.hashCode()); System.out.println(\"Displaying a1: \" + a1); System.out.println(\"Displaying a2: \" + a2); } catch (CloneNotSupportedException e) { e.printStackTrace(); } } } /*****************output***************/ gopal@gopal:~/Desktop/chegg$ javac GeometricObject.java gopal@gopal:~/Desktop/chegg$ javac Octagon.java gopal@gopal:~/Desktop/chegg$ javac App.java gopal@gopal:~/Desktop/chegg$ java App Area of a1 is 120.71067811865476 Perimeter of a1 is 40.0 Compare a1 and its clone a2: a1 and its clone a2 have the same area .

1. //operating system linux,ubuntu,Mac
/*********************GeometricObject.java**********************/
public abstract class GeometricObject {
private String color = "white";
private boolean filled;
// default constructure
public GeometricObject() {
super();
// TODO Auto-generated constructor stub
}
// construct a Geometric Object
// parameterized constructure
public GeometricObject(String color, boolean filled) {
this.color = color;
this.filled = filled;
}
/** Getter method for color */
public String getColor() {
return color;
}
/** Setter method for color */
public void setColor(String color) {
this.color = color;
}
/**
* Getter method for filled. Since filled is boolean, so the gret method
* name is isFilled
*/
public boolean isFilled() {
return filled;
}
/** Setter method for filled */
public void setFilled(boolean filled) {
this.filled = filled;
}

2. /** Abstract method for FindArea */
public abstract double findArea();
/** Abstract method for findPerimeter */
public abstract double findPerimeter();
}
/*****************************Octagon.java**************/
public class Octagon extends GeometricObject implements Cloneable, Comparable {
private double side;
/** construct a Octagon with specified side */
public Octagon(double side) {
super();
this.side = side;
}
/** Implement the abstract method findArea in GeometricObject */
@Override
public double findArea() {
double area = (2 + 4 / Math.sqrt(2)) * side * side;
return area;
}
/** Implement the abstract method findArea in findPerimeter */
@Override
public double findPerimeter() {
double perimeter = 8 * side;
return perimeter;
}
/** Implement the compareTo method in Comparable interface */
@Override
public int compareTo(Object o) {
// TODO Auto-generated method stub
return 0;
}
public Object clone() throws CloneNotSupportedException {
return super.clone();
}

3. }
/*******************App.java*******************/
public class App {
public static void main(String[] args) {
Octagon a1 = new Octagon(5);//creating object of octagon
System.out.println("Area of a1 is " + a1.findArea());
System.out.println("Perimeter of a1 is " + a1.findPerimeter());
Object a2;
try {
a2 = a1.clone();
String result = (a1.compareTo(a2) == 0) ? "a1 and its clone a2 have the same area"
: "a1 and its clone a2 have different areas";
System.out.println("Compare a1 and its clone a2: t " + result);
System.out.println("Hashcode of a1: " + a1.hashCode());
System.out.println("Hashcode of a2: " + a2.hashCode());
System.out.println("Displaying a1: " + a1);
System.out.println("Displaying a2: " + a2);
} catch (CloneNotSupportedException e) {
e.printStackTrace();
}
}
}
/*****************output***************/
gopal@gopal:~/Desktop/chegg$ javac GeometricObject.java
gopal@gopal:~/Desktop/chegg$ javac Octagon.java
gopal@gopal:~/Desktop/chegg$ javac App.java
gopal@gopal:~/Desktop/chegg$ java App
Area of a1 is 120.71067811865476
Perimeter of a1 is 40.0
Compare a1 and its clone a2:
a1 and its clone a2 have the same area
Hashcode of a1: 1808253012
Hashcode of a2: 589431969

4. Displaying a1: Octagon@6bc7c054
Displaying a2: Octagon@232204a1
Solution
//operating system linux,ubuntu,Mac
/*********************GeometricObject.java**********************/
public abstract class GeometricObject {
private String color = "white";
private boolean filled;
// default constructure
public GeometricObject() {
super();
// TODO Auto-generated constructor stub
}
// construct a Geometric Object
// parameterized constructure
public GeometricObject(String color, boolean filled) {
this.color = color;
this.filled = filled;
}
/** Getter method for color */
public String getColor() {
return color;
}
/** Setter method for color */
public void setColor(String color) {
this.color = color;
}
/**
* Getter method for filled. Since filled is boolean, so the gret method
* name is isFilled
*/
public boolean isFilled() {
return filled;
}

5. /** Setter method for filled */
public void setFilled(boolean filled) {
this.filled = filled;
}
/** Abstract method for FindArea */
public abstract double findArea();
/** Abstract method for findPerimeter */
public abstract double findPerimeter();
}
/*****************************Octagon.java**************/
public class Octagon extends GeometricObject implements Cloneable, Comparable {
private double side;
/** construct a Octagon with specified side */
public Octagon(double side) {
super();
this.side = side;
}
/** Implement the abstract method findArea in GeometricObject */
@Override
public double findArea() {
double area = (2 + 4 / Math.sqrt(2)) * side * side;
return area;
}
/** Implement the abstract method findArea in findPerimeter */
@Override
public double findPerimeter() {
double perimeter = 8 * side;
return perimeter;
}
/** Implement the compareTo method in Comparable interface */
@Override
public int compareTo(Object o) {
// TODO Auto-generated method stub
return 0;

6. }
public Object clone() throws CloneNotSupportedException {
return super.clone();
}
}
/*******************App.java*******************/
public class App {
public static void main(String[] args) {
Octagon a1 = new Octagon(5);//creating object of octagon
System.out.println("Area of a1 is " + a1.findArea());
System.out.println("Perimeter of a1 is " + a1.findPerimeter());
Object a2;
try {
a2 = a1.clone();
String result = (a1.compareTo(a2) == 0) ? "a1 and its clone a2 have the same area"
: "a1 and its clone a2 have different areas";
System.out.println("Compare a1 and its clone a2: t " + result);
System.out.println("Hashcode of a1: " + a1.hashCode());
System.out.println("Hashcode of a2: " + a2.hashCode());
System.out.println("Displaying a1: " + a1);
System.out.println("Displaying a2: " + a2);
} catch (CloneNotSupportedException e) {
e.printStackTrace();
}
}
}
/*****************output***************/
gopal@gopal:~/Desktop/chegg$ javac GeometricObject.java
gopal@gopal:~/Desktop/chegg$ javac Octagon.java
gopal@gopal:~/Desktop/chegg$ javac App.java
gopal@gopal:~/Desktop/chegg$ java App
Area of a1 is 120.71067811865476
Perimeter of a1 is 40.0

7. Compare a1 and its clone a2:
a1 and its clone a2 have the same area
Hashcode of a1: 1808253012
Hashcode of a2: 589431969
Displaying a1: Octagon@6bc7c054
Displaying a2: Octagon@232204a1