Create a Class containing a static method that can be used for future programs a
ID: 3571691 • Letter: C
Question
Create a Class containing a static method that can be used for future programs and as practice for creating future methods. The method must use the given Method header and must have java documentation. It should also include comments inside the method where appropriate.
1.) Determine If a Positive Integer is Prime Method Header: public static boolean isPrime(int number)
A positive integer is considered prime if its only be divided evenly by 1 and itself. This method should take in an integer and determine if it is a prime number. If the number is prime the method should return true otherwise, it should return false.
Hint: 2 is the smallest prime number, so any number below 2 is not a prime.
Explanation / Answer
CheckPrime.java
public class CheckPrime {
/* This method will check whether the number is prime or not
* Params :integer type number
* Return :boolean value.
*/
public static boolean isPrime(int number) {
if(number<2)
return false;
// If the user entered number is '2' return true
else if(number == 2)
return true;
for (int i = 2; i * i <= number; i++) {
if (number % i == 0)
return false;
}
return true;
}
}
____________________________
TestClass.java
import java.util.Scanner;
public class TestClass {
public static void main(String[] args) {
//Declaring variables
int number;
boolean bool;
//Scanner class object is used to read the inputs entered by the user
Scanner sc=new Scanner(System.in);
/* This loop continues to execute until
* the user enters a positive number
*/
while(true)
{
//Getting the number entered by the user
System.out.print("Enter a positive number :");
number=sc.nextInt();
if(number<0)
{
//Displaying the error message
System.out.println("** Invalid.Number Must be Positive **");
continue;
}
else
break;
}
//calling the method by passing the number as argument
bool = CheckPrime.isPrime(number);
/* If the returned 'bool' value is true
* Then display is prime message
* If not,display not a prime
*/
if (bool)
System.out.println(number+" is Prime");
else
System.out.println(number+" is not Prime");
}
}
____________________________
_______________________
Output:
Enter a positive number :1
1 is not Prime
_______________________
Output:
Enter a positive number :19
19 is Prime
_______________________
Output:
Enter a positive number :15
15 is not Prime
_______________________
Output:
Enter a positive number :-5
** Invalid.Number Must be Positive **
Enter a positive number :37
37 is Prime
______Thank You