In fact, I do not think CPs can really return their own Cell implementation which is not an ExtendedCell, we will call PrivateCellUtil.setSequenceId and setTimestamp at server side, if the Cell is not an ExtendedCell we will throw IOException...
I guess the only place where it is safe to return a customized Cell is in filter implementation, in getNextCellHint, where we will only use it to seek the scanners without storing it anywhere... Reid Chan <reidchan0...@gmail.com> 于2024年6月13日周四 10:56写道： > > It may affect Phoenix, as it is CPs related, at least for branch-2. > > Let's wait and see if there are any comments from them > > > --- > > Best regards, > R.C > > > > On Tue, Jun 11, 2024 at 4:19 PM Duo Zhang <zhang...@apache.org> wrote: > > > We have several deprecated methods in Cell interface, like > > getSequenceId and tag related ones, which are marked as deprecated > > since 2.0.0 and should be removed in 3.0.0. Most of them are marked as > > deprecated in HBASE-19112. > > > > After investigating, I found that it is not an easy work... > > > > We have 3 levels for the Cell interface > > > > Cell -> RawCell -> ExtendedCell > > > > Where Cell is the Public API for client side usage, RawCell is for CPs > > where we expose the tag related APIs, and ExtendedCell is for server > > side usage, where we expose all the internal stuff, like sequence id. > > > > In HBASE-19550, we introduced a CellWrapper as we think maybe CPs will > > return a Cell which is not an ExtendedCell at server side, we need to > > wrap it so at server side we always get an ExtendedCell. So if we > > remove the tag and sequence id related methods, CellWrapper will be > > broken. > > > > For me, I do not think we need the CellWrapper. In general, all actual > > Cell implementation classes in our code base implement the > > ExtendedCell interface, i.e, we can simply consider all Cells are > > actually ExtendedCells. The only reason we introduce the Cell > > interface, is to hide internal stuff from client public API, does not > > mean we want users to implement their own Cell. > > > > So the plan is to change server side code use ExtendedCell as much as > > possible in HBASE-28644, a draft PR is already there for review[1]. > > This will be landed to both 3.x and at least branch-2(I'm not sure if > > it worth to also land on branch-2.6 and branch-2.5). > > And starting from 3.0.0, we should make clear that all Cell instances > > should be created via the CellBuilder related APIs, other Cell > > implementations are not allowed. So on 3.0.0, we should treat Cell as > > ExtendedCell everywhere in our code base, and also remove the > > CellWrapper class, then we could finally remove the deprecated methods > > in the Cell interface. > > > > Thoughts? > > > > Thanks. > > > > 1. https://github.com/apache/hbase/pull/5976 > >
