code: public static String xor(String string, int key) {
          char[] encrypt = string.toCharArray();
          for (int i = 0; i < encrypt.length; i++) {
              encrypt[i] = (char) (encrypt[i] ^ key);
          }
          return new String(encrypt);
      }
docs: 异或加密
  
  @param string {@link String}
  @param key {@link Integer}
  
  @return {@link String}