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I want a program that repeatedly prompts the user to input a number and then prints whether that number is prime or not. This works once, then on the next iteration it gives a No Such Element Exception before the user can enter another input.

I've tried using IF statements with hasNext() or hasNextInt() but those never seem to be true for the same reason. I also tried using a FOR loop to iterate a fixed number of times but that gives the same error. Why is this allowing for user input the first time it loops through but not after that?

public static void primeChecker() 
{ 
      Scanner scan = new Scanner(System.in);
      System.out.print("Please enter a number: ");
      int number = scan.nextInt();
      if (isPrime(number)) {
        System.out.println(number + " is prime");
      }
      else {
        System.out.println(number + " is not prime");
      }
      scan.close();
}

public static void main(String[] args) 
{
    int y=1;
    while(y!=0)
    {
      primeChecker();
}
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1 Answer

Remove scan.close();, as it is closing the scanner.


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