Valid Palindrome II

Given a non-empty string s, you may delete at most one character. Judge whether you can make it a palindrome.

Example 1:

Input: "aba"
Output: True

Example 2:

Input: "abca"
Output: True
Explanation: You could delete the character 'c'.

Note:

1. The string will only contain lowercase characters a-z. The maximum length of the string is 50000.

class Solution {
    public boolean validPalindrome(String s) {
        int i = 0, j = s.length() - 1;
        while (i < j) {
            if (s.charAt(i) != s.charAt(j)) {
                boolean ans = isPalindrome(s, i, j - 1) || isPalindrome(s, i + 1, j);
                return ans;
            }
            i++;
            j--;
        }
        return true;
    }

    public boolean isPalindrome(String str, int i, int j) {
        while (i <= j) {
            if (str.charAt(i) != str.charAt(j))
                return false;
            i++;
            j--;
        }
        return true;
    }
}