将base64编码的字节数组解码为(负)十进制值(Java to Python)

import java.util.Base64;

public class Base64Decoder {
    public static void main(String[] args) {
        String base64String = "SGVsbG8gV29ybGQh"; // base64编码的字符串

        byte[] decodedBytes = Base64.getDecoder().decode(base64String);
        int decimalValue = 0;
        for (byte b : decodedBytes) {
            decimalValue = (decimalValue << 8) | (b & 0xFF);
        }

        System.out.println("Decoded decimal value: " + decimalValue);
    }
}

import base64

base64_string = "SGVsbG8gV29ybGQh"  # base64编码的字符串

decoded_bytes = base64.b64decode(base64_string)
decimal_value = int.from_bytes(decoded_bytes, byteorder='big', signed=True)

print("Decoded decimal value:", decimal_value)