Thrift2 was supposed to be the future -- an API like the native java API -- but it never got the support needed to make it a superset of thrift1. Meantime folks are running thrift1 in production and patching it as they need extra calls and fixes.
While we have two thrifts, thrift1 and thrift2, the latter of which we are afraid to recommend because we do not know of any prod install, we sew confusion ("Which should I use?", "Doc only talks about 'thrift'?"). HBASE-8184 is a patch to remove thrift2 until it gets a sponsor who can move it beyond thrift1 . I already have a +1 to remove. Will let the issue stew a day or two in case objection to thrift2 going away. St.Ack