I understood the plan for avoiding JDK7-specific features in our code, and your suggestion to add an extra Jenkins job is a great way to guard against that. The thing I haven't seen discussed yet is how downstream projects will continue to consume our built artifacts. If a downstream project upgrades to pick up a bug fix, and the jar switches to 1.7 class files, but their project is still building with 1.6, then it would be a nasty surprise.
These are the options I see: 1. Make sure all other projects upgrade first. This doesn't sound feasible, unless all other ecosystem projects have moved to JDK7 already. If not, then waiting on a single long pole project would hold up our migration indefinitely. 2. We switch to JDK7, but run javac with -target 1.6 until the whole ecosystem upgrades. I find this undesirable, because in a certain sense, it still leaves a bit of 1.6 lingering in the project. (I'll assume that end-of-life for JDK6 also means end-of-life for the 1.6 bytecode format.) 3. Just declare a clean break on some version (your earlier email said 2.5) and start publishing artifacts built with JDK7 and no -target option. Overall, this is my preferred option. However, as a side effect, this sets us up for longer-term maintenance and patch releases off of the 2.4 branch if a downstream project that's still on 1.6 needs to pick up a critical bug fix. Of course, this is all a moot point if all the downstream ecosystem projects have already made the switch to JDK7. I don't know the status of that off the top of my head. Maybe someone else out there knows? If not, then I expect I can free up enough in a few weeks to volunteer for tracking down that information. Chris Nauroth Hortonworks http://hortonworks.com/ On Wed, Jun 25, 2014 at 3:12 PM, Alejandro Abdelnur <t...@cloudera.com> wrote: > Chris, > > Compiling with jdk7 and doing javac -target 1.6 is not sufficient, you are > still using jdk7 libraries and you could use new APIs, thus breaking jdk6 > both at compile and runtime. > > you need to compile with jdk6 to ensure you are not running into that > scenario. that is why i was suggesting the nightly jdk6 build/test jenkins > job. > > > On Wed, Jun 25, 2014 at 2:04 PM, Chris Nauroth <cnaur...@hortonworks.com> > wrote: > > > I'm also +1 for getting us to JDK7 within the 2.x line after reading the > > proposals and catching up on the discussion in this thread. > > > > Has anyone yet considered how to coordinate this change with downstream > > projects? Would we request downstream projects to upgrade to JDK7 first > > before we make the move? Would we switch to JDK7, but run javac -target > > 1.6 to maintain compatibility for downstream projects during an interim > > period? > > > > Chris Nauroth > > Hortonworks > > http://hortonworks.com/ > > > > > > > > On Wed, Jun 25, 2014 at 9:48 AM, Owen O'Malley <omal...@apache.org> > wrote: > > > > > On Tue, Jun 24, 2014 at 4:44 PM, Alejandro Abdelnur <t...@cloudera.com > > > > > wrote: > > > > > > > After reading this thread and thinking a bit about it, I think it > > should > > > be > > > > OK such move up to JDK7 in Hadoop > > > > > > > > > I agree with Alejandro. Changing minimum JDKs is not an incompatible > > change > > > and is fine in the 2 branch. (Although I think it is would *not* be > > > appropriate for a patch release.) Of course we need to do it with > > > forethought and testing, but moving off of JDK 6, which is EOL'ed is a > > good > > > thing. Moving to Java 8 as a minimum seems much too aggressive and I > > would > > > push back on that. > > > > > > I'm also think that we need to let the dust settle on the Hadoop 2 line > > for > > > a while before we talk about Hadoop 3. It seems that it has only been > in > > > the last 6 months that Hadoop 2 adoption has reached the main stream > > users. > > > Our user community needs time to digest the changes in Hadoop 2.x > before > > we > > > fracture the community by starting to discuss Hadoop 3 releases. > > > > > > .. Owen > > > > > > > -- > > CONFIDENTIALITY NOTICE > > NOTICE: This message is intended for the use of the individual or entity > to > > which it is addressed and may contain information that is confidential, > > privileged and exempt from disclosure under applicable law. If the reader > > of this message is not the intended recipient, you are hereby notified > that > > any printing, copying, dissemination, distribution, disclosure or > > forwarding of this communication is strictly prohibited. If you have > > received this communication in error, please contact the sender > immediately > > and delete it from your system. Thank You. > > > > > > -- > Alejandro > -- CONFIDENTIALITY NOTICE NOTICE: This message is intended for the use of the individual or entity to which it is addressed and may contain information that is confidential, privileged and exempt from disclosure under applicable law. If the reader of this message is not the intended recipient, you are hereby notified that any printing, copying, dissemination, distribution, disclosure or forwarding of this communication is strictly prohibited. If you have received this communication in error, please contact the sender immediately and delete it from your system. Thank You.
