Java基础String类-字符串反转

public class HomeworkTest03 {
    public static void main(String[] args) {
        Scanner s = new Scanner(System.in);
        System.out.print("请输入你要反转的字符串：");
        String s1 = s.next();
        System.out.println(reverse(s1));
    }
    /**
     * 调用String对象的charAt方法，将字符串从后往前依次取出来
     * 然后添加到StringBuffer当中去，在转换成String对象
     *
     * @param str
     * @return
     */
    public static String reserve(String str) {
        StringBuffer sb = new StringBuffer();
        for (int i = str.length() - 1; i >= 0; i--) {
            sb.append(str.charAt(i));
        }
        return sb.toString();
    }
    public static String reverse(String str) {
        StringBuffer s = new StringBuffer(str);
        s.reverse();
        return s.toString();
    }
    public static String reverse01(String s) {
        String s1 = "";
        for (int i = s.length(); i>=0;i++) {
            char c = s.charAt(i);
            s1 += c;
        }
        return s1;
    }
}