Hi Colin, Indeed, Hadoop was one of a few projects I mentioned in the original thread. When is Hadoop 3 expected to be stable?
Examples are Cassandra[4], Lucene[5], Akka[6], Hadoop 3[7], > Jetty[8], Eclipse[9], IntelliJ[10] and many others[11]. Even Android will > support Java 8 in the next version (although it will take a while before > most phones will use that version sadly). > ... [4] https://github.com/apache/cassandra/blob/trunk/README.asc > [5] https://lucene.apache.org/#highlights-of-this-lucene-release-include > [6] http://akka.io/news/2015/09/30/akka-2.4.0-released.html > [7] https://issues.apache.org/jira/browse/HADOOP-11858 > [8] https://webtide.com/jetty-9-3-features/ > [9] http://markmail.org/message/l7s276y3xkga2eqf > [10] > > https://intellij-support.jetbrains.com/hc/en-us/articles/206544879-Selecting-the-JDK-version-the-IDE-will-run-under > [11] http://markmail.org/message/l7s276y3xkga2eqf Ismael On Wed, Dec 7, 2016 at 1:10 AM, Colin McCabe <cmcc...@apache.org> wrote: > Interestingly, Hadoop 3.x will require Java 8 or later. > > From http://hadoop.apache.org/docs/r3.0.0-alpha1/ > > Minimum required Java version increased from Java 7 to Java 8 > > All Hadoop JARs are now compiled targeting a runtime version of Java 8. > Users still > > using Java 7 or below must upgrade to Java 8. > > Of course, there are still many people using Hadoop 2.x and > distributions derived from it, and will be for a while. > > best, > Colin > > > On Mon, Nov 28, 2016, at 11:21, Ismael Juma wrote: > > By supporting two Java versions, I mean supporting the two most recent > > ones. So, we'd only drop support for Java 7 after Java 9 is released, but > > no sooner (independently of how old or unsupported a particular version > > is). An alternative approach is to drop support a defined amount of time > > after a particular version is EOL'd. > > > > With respect to the question about the cost of supporting multiple Java > > versions: it is OK to compile with the oldest version, but we definitely > > need to run the unit, integration, system and performance tests with all > > supported versions. The Java team strives to maintain compatibility, but > > regressions and behaviour differences are not uncommon across major > > releases (and sometimes update releases). Projects like Lucene are very > > good at hitting JIT bugs and they actually test against JDK EA snapshot > > builds in the hope of triggering them before a stable release. > > > > Ismael > > > > On Mon, Nov 28, 2016 at 6:39 PM, radai <radai.rosenbl...@gmail.com> > > wrote: > > > > > i dont completely understand the meaning behind supporting 2 java > versions. > > > given java's pretty good about backwards compatibility if you build > against > > > the oldest JDK you support (say 8) it should run on anything newer > (say 9). > > > what am i missing? > > > > > > On Mon, Nov 28, 2016 at 4:06 AM, Ismael Juma <ism...@juma.me.uk> > wrote: > > > > > > > I think there are 3 main points that can be taken from that > discussion > > > with > > > > regards to the timing: > > > > > > > > 1. We should do the switch no earlier than Kafka's next major version > > > bump > > > > (i.e. 0.11.0.0 at this point) > > > > 2. Some would prefer to support two Java versions, so we'd have to > wait > > > > until Kafka's next major version bump _after_ Java 9 is released. > Java 9 > > > is > > > > currently scheduled to be released in July 2017. I like the > guideline of > > > > supporting two Java versions at a time, but multiple delays to Java 8 > > > and 9 > > > > combined with huge improvements in Java 8 could provide the basis > for an > > > > exception. > > > > 3. Some would prefer the clients jar to support Java 7 for longer as > > > there > > > > are cases where it is hard to upgrade all clients to use Java 8 > (maybe > > > they > > > > run in an older App Server that only supports Java 7, for example). > > > > > > > > It seems like 1 is a hard requirement while 2 and 3 are less so. > Given > > > > that, I was planning to restart the conversation when we have a plan > to > > > > bump Kafka's major version (a message format change would quality > > > > typically). > > > > > > > > Ismael > > > > > > > > On Thu, Nov 10, 2016 at 7:03 PM, Joel Koshy <jjkosh...@gmail.com> > wrote: > > > > > > > > > http://markmail.org/message/gnrn5ccql7a2pmc5 > > > > > We can bump that up to revisit the discussion. That thread didn't > have > > > > any > > > > > closure, but has a lot of background information. > > > > > > > > > > On Thu, Nov 10, 2016 at 10:37 AM, Sean McCauliff < > > > > sean.mccaul...@gmail.com > > > > > > > > > > > wrote: > > > > > > > > > > > Wait for JDK 9 which is supposed to be 4-5 months from now? > > > > > > > > > > > > Sean > > > > > > > > > > > > On Thu, Nov 10, 2016 at 10:23 AM, radai < > radai.rosenbl...@gmail.com> > > > > > > wrote: > > > > > > > with java 7 being EOL'ed for more than a year and a half now > (apr > > > > 2015, > > > > > > see > > > > > > > http://www.oracle.com/technetwork/java/eol-135779.html) i was > > > > > wondering > > > > > > if > > > > > > > there's an official plan/timetable for transitioning the kafka > > > > codebase > > > > > > > over to java 8? > > > > > > > > > > > > > > > > > > >
