Check non-numeric characters in string

Question

I want to check whether the String contains only numeric characters or it contains alpha-numeric characters too.

I have to implement this check in database transacti

Answer 1

Just Googling, I found out this link

 public boolean containsOnlyNumbers(String str) {        
        //It can't contain only numbers if it's null or empty...
        if (str == null || str.length() == 0)
            return false;

        for (int i = 0; i < str.length(); i++) {

            //If we find a non-digit character we return false.
            if (!Character.isDigit(str.charAt(i)))
                return false;
        }

        return true;
    }

Edit: A RegExp to check numeric should be :

return yourNumber.matches("-?\\d+(.\\d+)?");