Problem Details
I am trying to reverse only the vowels in a given string and return the modified String.

The vowels are ‘a’, ‘e’, ‘i’, ‘o’, and ‘u’, and they can appear in both lower and upper cases, more than once.

Example 1:

Input: s = “hello” Output: “holle”

Example 2:

Input: s = “leetcode” Output: “leotcede”

Constraints:

1 <= s.length <= 3 * 105 s consist of printable ASCII characters.

My Approach

package test.test;

import java.util.Arrays;
import java.util.HashSet;
import java.util.Set;

public class ReverseVowel4 {
    public static String reverseVowels(String s) {

        Set<Character> set = new HashSet<>(Arrays.asList('a', 'e', 'i', 'o', 'u', 'A', 'E', 'I', 'O', 'U'));

        char[] charArray = s.toCharArray();
        int i = 0;
        int j = s.length() - 1;

        while (i < j) {
            if (set.contains(charArray[i]) && set.contains(charArray[j])) {

                char temp = charArray[i];
                charArray[i] = charArray[j];
                charArray[j] = temp;
                i++;
                j--;
            } else if (set.contains(s.charAt(i)) && !set.contains(s.charAt(j))) {
                j--;
            } else if (!set.contains(s.charAt(i)) && set.contains(s.charAt(j))) {
                i++;
            } else {
                i++;
                j--;
            }
        }
        return new String(charArray);
    }

    public static void main(String[] args) {
        String ss = reverseVowels("aA");
        System.out.println(ss);
    }

}

Question

Is this the most efficient way to reverse the vowels in a string given the constraints, or is there a better approach? If there are any optimizations or alternative methods, I would appreciate any suggestions.