LeetCode之Reverse String

1、题目：

Write a function that takes a string as input and returns the string reversed.

Example:
Given s = "hello", return "olleh".

2、代码实现：

代码实现1:

    public static String reverseString(String s) {        if (s == null) {            return null;        }        if (s.length() == 0) {            return "";        }        int length = s.length();        char[] chars = s.toCharArray();        String result = "";        for (int i = chars.length - 1; i >=0; --i) {            result += chars[i];        }        return result;    }

代码实现2:

    public String reverseString(String s) {        return new StringBuffer(s).reverse().toString();    }