How to compile a cross-platform jar locally

[cuibo01]

https://github.com/ververica/frocksdb/blob/FRocksDB-6.20.3/java/RELEASE.md
I compiled frocksdb on centos7.6 according to the document, but encountered many errors.

First, I ran the make jclean clean rocksdbjavastaticreleasedocker command and encountered the following error
CFLAGS='-fPIC ' LDFLAGS=' ' ./configure --static --archs='-arch x86_64' && make
Checking for gcc...
Compiler error reporting is too harsh for ./configure (perhaps remove -Werror).
** ./configure aborting.

and then delete all -arch x86_64, and encountered the error
docker run --rm --name rocksdb_linux_x86-be --platform linux/386 --attach stdin --attach stdout --attach stderr --volume /root/.m2:/root/.m2:ro --volume pwd:/rocksdb-host:ro --volu-java-target --env DEBUG_LEVEL=0 evolvedbinary/rocksjava:centos6_x86-be /rocksdb-host/java/crossbuild/docker-build-linux-centos.sh
unknown flag: --platform

Is there any detailed document or CI for reference? thank you