In Java, byte arrays can store negative values, because the value range of the byte type in Java is between -128 and 127, while in Python3, the value range of bytes is 0 to 256.
Java： -127~128
Python：0~256
In some scenarios, such as AES encryption, the definition of parameter values such as Key and IV (offset) will be used. In Java, it may be as follows:
public static byte[] iv = new byte[] {
1, 3, 8, 22, -13, 125, -40, -124, -27, -10, 57, 13, 46, 22, -3, 5 };
At this time, if you need to implement the same encryption algorithm through Python3, there will be a problem, that is, the negative value in the above Java code cannot be directly expressed in Python3.
Faced with this situation, the following methods can be used for conversion in Python3:
iv = [1, 3, 8, 22, -13, 125, -40, -124, -27, -10, 57, 13, 46, 22, -3, 5]
iv_byte = bytes(i % 256 for i in iv)
After passing in the corresponding AES algorithm function in Python, the corresponding encryption results are consistent.