The Art of Software Testing, Second Edition

Appendix A. Sample Extreme Testing Application

1.check4Prime.java

To compile:

&> javac check4Prime.java

To run:

&> java -cp check4Prime 5
Yippeee... 5 is a prime number!

&> java -cp check4Prime 10
Bummer.... 10 is NOT a prime number!

&> java -cp check4Prime A
Usage: check4Prime x
       -- where 0<=x<=1000

Source code:

//check4Prime.java
//Imports
import java.lang.*;

public class check4Prime {
  static final int max = 1000;   // Set upper bounds.
  static final int min = 0;      // Set lower bounds.
  static int input =0;           // Initialize input variable.

public static void main (String [] args) {

    //Initialize class object to work with
    check4Prime check = new check4Prime();

    try{
    //Check arguments and assign value to input variable
      check.checkArgs(args);

    //Check for Exception and display help
    }catch (Exception e) {
      System.out.println("Usage: check4Prime x");
      System.out.println("       -- where 0<=x<=1000");
  System.exit(1);
}

//Check if input is a prime number
if (check.primeCheck(input))
  System.out.println("Yippeee... " + input + " is a prime number!");
else
  System.out.println("Bummer... " + input + " is NOT a prime number!");

} //End main

//Calculates prime numbers and compares it to the input
public boolean primeCheck (int num) {

  double sqroot = Math.sqrt(max);     // Find square root of n

//Initialize array to hold prime numbers
boolean primeBucket [] = new boolean [max+1];

//Initialize all elements to true, then set non-primes to false
for (int i=2; i<=max; i++) {
  primeBucket[i]=true;
}

//Do all multiples of ...