345. Reverse Vowels of a String

public static String reverseVowels(String s) { String vowels = "aeiouAEIOU"; char[] tmp = s.toCharArray(); int i = 0, j = s.length() -1; while(i < j) { while(i < j && vowels.indexOf(tmp[i]) < 0) i++; while(i < j && vowels.indexOf(tmp[j]) < 0) j--; if(i < j) { char tmpChar = tmp[i]; tmp[i] = tmp[j]; tmp[j] = tmpChar; i++; j--; } } return new String(tmp); }