BEAM-8822 Hadoop client version 2.8.5 from 2.7 is merged. It's time to upgrade Guava.
CharMatcher.DIGIT, used by org.apache.cassandra.io.sstable.format.SSTableFormat, is removed since Guava 26.0. 25.1 is the latest version:
Guava has 2 variations "-jre" for Java8 (stream/lambda support) and "-android" for Java7. Gcsio:1.9.16, which Beam has not have in dependency tree yet, needs ImmutableSet.toImmutableSet() which is available in Guava "-jre".
The latest cassandra-all release is "4.0-alpha2", which is still alpha. This version depends on guava 27.0-jre (link).
Non-alpha version is 3.11.5 https://search.maven.org/artifact/org.apache.cassandra/cassandra-all/3.11.5/jar, which still relies on Guava 18 and it still has reference to DIGIT:
Guava 19 has digit() method. Not Guava 18.