Palindrome with recursion; index out of bound

Question

I'm trying to write a function that checks whether a string variable is a palindrome or not. I can't find the reason this code throws IndexOutOfBoundException. I've tried to use examples so as to follow the result, but I still can't see where the exception is from.

public static boolean palindrome(String s) {
    if (s.charAt(0) == s.charAt(s.length() - 1)) {
        if (s.length() > 2) {       
            StdOut.print(s.substring(1, s.length() - 2));
            palindrome(s.substring(1, s.length() - 2));
        } else
            return true;
    }
    return false;
}

Answer 1

Try this:

public static boolean palindrome(String s)
{
    if (s.length() < 2)
        return true;
    if (s.charAt(0) != s.charAt(s.length()-1))
        return false;
    return palindrome(s.substring(1,s.length()-1));
}