在Java中如何将十六进制反转为反向十六进制？

Question

我从下面的另一个问题中看到了一个代码，但我不知道如何利用它。

let hex_string: String = String::from("d59c168e05df4757");
let string_to_bytes = parse_hex(&hex_string);
println!("Hex string as bytes: {:?}", string_to_bytes); //Prints: [213, 
156, 22, 142, 5, 223, 71, 87]
let mut bytes_reversed = Vec::new();
for i in string_to_bytes.iter().rev() {
    bytes_reversed.push(i);
}
println!("Bytes reversed: {:x?}", bytes_reversed); //Prints: [57, 47, 
   df, 5, 8e, 16, 9c, d5]

Answer 1

使用StringBuilder:

StringBuilder sb = new StringBuilder(hexString);

字符的反向对：

for (int i = 0; i < sb.length(); i += 2) {
  char tmp = sb.charAt(i);
  sb.setCharAt(i, sb.charAt(i+1));
  sb.setCharAt(i+1, tmp);
}

然后把整件事颠倒过来：

sb.reverse();

String reversed = sb.toString();

for (int i = 0, j = sb.length() - 2; i < j; i += 2, j -= 2) {
  for (int d = 0; d < 2; ++d) {
    char tmp = sb.charAt(i + d);
    sb.setCharAt(i + d, sb.charAt(j + d));
    sb.setCharAt(j + d, tmp);
  }
}

String reversed =
    new StringBuilder(8)
        .append(hexString, 6, 8)
        .append(hexString, 4, 6)
        .append(hexString, 2, 4)
        .append(hexString, 0, 2)
        .toString();