P4
The existing CRC32 and CRC32C in java.util.zip have only the default constructor and reset method to an initial value zero.
There are applications where non-zero initial values are useful: resuming the running checksum, concatenating inputs to a common header, or getting the initial value from a transmission. In these cases, restarting from a non-zero value is expensive or impossible.
There are CRC32 initialization APIs provided in zlib and Python.
https://github.com/madler/zlib/blob/04f42ceca40f73e2978b50e93806c2a18c1281fc/crc32.c#L1072
https://docs.python.org/3/library/zlib.html#zlib.crc32
There are applications where non-zero initial values are useful: resuming the running checksum, concatenating inputs to a common header, or getting the initial value from a transmission. In these cases, restarting from a non-zero value is expensive or impossible.
There are CRC32 initialization APIs provided in zlib and Python.
https://github.com/madler/zlib/blob/04f42ceca40f73e2978b50e93806c2a18c1281fc/crc32.c#L1072
https://docs.python.org/3/library/zlib.html#zlib.crc32