Exploring Variable Length Parameter Lists

The fileParameters.javacontains a program to test the variable length methodaveragefrom Section 7.5 of the text. Note thataveragemust be a static method since it is called from the static methodmain.

1. Compile and run the program.
2. Add a call to find the average of a single integer, say 13. Print the result of the call.
3. Add a call with an empty parameter list and print the result. Is the behavior what you expected?
4. Add a methodmaximumthat takes a variable number of integer parameters and returns themaximumof the parameters. Invoke your method on each of the parameter lists used for the average function.

//*******************************************************

// Parameters.java

//

// Illustrates the concept of a variable parameter list.

//*******************************************************

import java.util.Scanner;s

public class Parameters

{

//-----------------------------------------------

// Calls the average method with

// different numbers of parameters.

//-----------------------------------------------

public static void main(String[] args)

{

double mean1, mean2;

mean1 = average(42, 69, 37);

mean2 = average(35, 43, 93, 23, 40, 21, 75);

System.out.println ("mean1 = " + mean1);

System.out.println ("mean2 = " + mean2);

}

//----------------------------------------------

// Returns the average of its parameters.

//----------------------------------------------

public static double average (int ... list)

{

double result = 0.0;

if (list.length != 0)

{

int sum = 0;

for (int num: list)

sum += num;

result = (double)sum / list.length;

}

return result;

}

}