判断是否定是回文字

public static boolean IsHuiwen(String word) {
            StringBuilder sb = new StringBuilder(word);
            String wordReverse = sb.reverse().toString();
            return wordReverse.equals(word);
        }
        
        //不需要任何方法判断是否是回文
        public static boolean IsHuiwen2(String word) {
            boolean isHuiwen = true;
            int len = word.length();
            //levvel
            for(int i = 0; i < len / 2; i++)
            {
                if(word.charAt(i) != word.charAt(len - 1 - i))
                {
                    isHuiwen = false;
                    break;
                }
            }
            return isHuiwen;
        }
        public static void main(String[] args) {
//        System.out.println("level".charAt(0));
            System.out.println(IsHuiwen2("levveel"));
        }