parallelCollectionScan command against mongos

The MongoDB java driver page[1] says that the command is not supported via mongos.
Is that a driver limiation or MongoDB server limiation? If later, then are there any plans to support it?




It's a MongoDB server limitation. 



Any plans to support it? If so when? 



No plans, and I don't see a Jira issue for it either.  You can open one here: https://jira.mongodb.org/browse/SERVER.