Question

Write a full class definition for a class named Averager, and containing the following members: An data member named sum of type integer. An data member named count of type integer. A constructor with no parameters. The constructor initializes the data members sum and the data member count to 0. A function named getSum that accepts no parameters and returns an integer. getSum returns the value of sum. A function named add that accepts an integer parameter and returns no value. add increases the value of sum by the value of the parameter, and increments the value of count by one. A function named getCount that accepts no parameters and returns an integer. getCount returns the value of the count data member, that is, the number of values added to sum. A function named getAverage that accepts no parameters and returns a double. getAverage returns the average of the values added to sum. The value returned should be a value of type double (and therefore you must cast the data members to double prior to performing the division).

Answer 1

Answer:

//program in java.

import java.io.*;

class Averager {

   public static int sum;

   public static int count;    

   //constructor to initialize values

   Averager(){

       sum = 0;

       count = 0;

   }

   //Method to return Sum

   public static int getSum(){

       return sum;

   }

   //Method to add the value passed in parameter

   public static void add(int num){

       sum=sum+num;

       count=count+1;

   }

   //Method to return Count

   public static int getCount(){

       return count;

   }

   //Method to return Average

   public static double getAverage(){

//type casting is used

       return (double) sum / (double) count;

   }      

   //User Driven Input method to run the program

public static void main (String[] args)throws IOException {

    //Using BufferedReader class for reading input

    InputStreamReader x = new InputStreamReader(System.in);

    BufferedReader inp = new BufferedReader(x);

    int n;

    do{

 System.out.println("Enter your choice");

 System.out.println("1.getSum()");

 System.out.println("2.add()");

 System.out.println("3.getCount()");

 System.out.println("4.getAverage()");

 System.out.println("5.Exit");

 n=Integer.parseInt(inp.readLine());

 switch(n)

 {

     case 1 : int s = getSum();

              System.out.println("The Sum is " + s);

              break;

     case 2 : System.out.println("Enter the number to add");

              int num;

              num=Integer.parseInt(inp.readLine());

              add(num);

              break;

     case 3 : int c = getCount();

              System.out.println("The Count is " + c);

              break;

     case 4 : double avg = getAverage();

              System.out.println("The Average is " + avg);

              break;

     default : break;

 };

    }while(n!=5);

    System.out.println("Exiting");

}

}

Explanation :

Average() constructor is used for initialization. Method getSum() will return the value of sum. Method getCount() will return the count and method getAverage() will return the average. The average will be of double type. User driver input is designed to call the methods as and when required.

Input:

Enter your choice

1.getSum()

2.add()

3.getCount()

4.getAverage()

5.Exit

1

Output:

The Sum is 0