Question

a) Write out an abstract class to represent a ball. Include data fields to store the weight of the ball as a double value and the color of the ball as a String. Include a no-arg constructor as well as a two-arg constructor to set these two fields. Declare an abstract method, howToPlay(), which is to describe how the ball is used by printing this description to the command line.

Answer 1

Answer:

Check the explanation

Explanation:

//Ball.java

public abstract class Ball {

   double value;

   String color;

   public Ball() {

   }

   public Ball(double value, String color) {

       this.value = value;

       this.color = color;

   }

   public abstract void howToPlay();

}

////////////////////////////////////////////

//SoccerBall.java

public class SoccerBall extends Ball {

   public void howToPlay() {

       System.out.println("Description to how to play soccer ball");

   }

}

Answer 2

Answer:

See explaination

Explanation:

Code

abstract class Ball

{

double weight;

String color;

Ball()

{

this.weight=0;

this.color=" ";

System.out.println("Abstract class constructor");

}

Ball(double weight,String color)

{

this.weight=weight;

this.color=color;

System.out.println("Parameterized constructor of Abstract class with weight = "+weight+" color = "+color);

}

public abstract void howToPlay();

}

public class Baseball extends Ball {

int no;

String name;

int bat,hi ts;

Baseball() {

super(20,"red");

System.out.println("BaseBall class Constructor");

}

Baseball(int no,String name,int bat,int hi ts)

{

this.no=no;

this.name=name;

this.bat=bat;

this.hi ts=hi ts;

}

public void howToPlay()

{

System.out.println("How to play method weight = "+weight+ " color = "+color);

}

public void display()

{

System.out.println("Player no: "+no+" name = "+name+" numberAtbat = "+bat+" hi ts = "+hit s);

}

public static void main(String[] args) {

Baseball ob j = new Baseball();

Baseball ob j1 = new Baseball(1,"abc",1,3);

ob j.howToPlay();

ob j1.display();

}

}