What is a NumberFormatException and how can I fix it?

Question

Error Message:
Exception in thread \"main\" java.lang.NumberFormatException: For input string: \"Ace of Clubs\"
    at java.lang.NumberFormatException.forInputString         


        

Answer 1

Looks like cards[] is String array and you are trying to convert Ace of Clubs to Integer.

int first_value = Integer.parseInt(cards[index]);