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

java.lang.NumberFormatException 

occurs when you are trying to parse some input which not a Number string.

In your case your trying to parse a string (which not has number )as Integer. As its not possible NumberFormatException exception occured.

int first_value = Integer.parseInt(cards[index]);//cards[index] value should be //number string "123" not "abc"