Hi Flavio, To address your points:
1) It runs. That's fine. 2) It doesn't work to run a Java 8 compiled Flink job with Java 7 Flink cluster if you use Java 8 non-backwards-compatible features in your job. 3) I compile Flink daily with Java 8. Also, we have Travis CI tests which uses OpenJDK and OracaleJDK 7/8 to compile. I think there is something wrong with the configuration of your build setup. Cheers, Max On Thu, Feb 4, 2016 at 11:55 AM, Flavio Pompermaier <pomperma...@okkam.it> wrote: > I've tested several configurations (also changing my compilation to 1.7 but > then sesame 4 was causing the error [1]): > > Flink compiled with java 1.7 (default), runned within Eclipse with Java 8: > OK > Flink compiled with java 1.7 (default), runned the cluster with java 8: not > able to run my job compiled with java 1.8 and causing the reported exception > (unsupported major.minor version) > Flink compiled with java 1.8: not able to compile without the reported > modifications, but then the job was running fine > > I don't know if you ever tested all those configurations but I'm sure it > wasn't working when deployed in the cluster. > > [1] http://rdf4j.org/doc/4/release-notes/4.0.0.docbook?view > > On Thu, Feb 4, 2016 at 11:40 AM, Stephan Ewen <se...@apache.org> wrote: >> >> Hi! >> >> I am running Java 8 for a year without an issue. The code is compiled for >> target Java 7, but can be run with Java 8. >> User code that is targeted for Java 8 can be run if Flink is run with Java >> 8. >> >> The initial error you got was because you probably compiled with Java 8 as >> the target, and ran it with Java 7. >> >> I would just leave the target to be 1.7 and run it in a Java 8 JVM. User >> code can also be Java 8, that mixes seamlessly. >> >> Stephan >> >> >> On Thu, Feb 4, 2016 at 11:34 AM, Flavio Pompermaier <pomperma...@okkam.it> >> wrote: >>> >>> Anyone looking into this? Java 7 reached its end of life at april 2015 >>> with its last public update (numer 80) and the ability to run Java 8 jobs >>> would be more and more important in the future. IMHO, the default target of >>> the maven compiler plugin should be set to 1.8 in the 1.0 release. In most >>> of the cases this would be backward compatible and if it's not you can >>> always recompile it with 1.7 (but as an exception this time). >>> Obviously this is not urgent, I just wanted to point this out and >>> hopefully help someone else facing the same problem >>> >>> Best, >>> Flavio >>> >>> >>> On Wed, Feb 3, 2016 at 3:40 PM, Flavio Pompermaier <pomperma...@okkam.it> >>> wrote: >>>> >>>> I've fixed it changing the copy method in the TupleSerializer as follow: >>>> >>>> @Override >>>> public T copy(T from, T reuse) { >>>> for (int i = 0; i < arity; i++) { >>>> Object copy = fieldSerializers[i].copy(from.getField(i)); >>>> reuse.setField(copy, i); >>>> } >>>> return reuse; >>>> } >>>> >>>> And commenting line 50 in CollectionExecutionAccumulatorsTest: >>>> >>>> assertEquals(NUM_ELEMENTS, >>>> result.getAccumulatorResult(ACCUMULATOR_NAME)); >>>> >>>> I hope it helps.. >>>> >>>> On Wed, Feb 3, 2016 at 3:12 PM, Flavio Pompermaier >>>> <pomperma...@okkam.it> wrote: >>>>> >>>>> I've checked the compiled classes with javap -verbose and indeed they >>>>> had a major.verion=51 (java 7). >>>>> So I've changed the source and target to 1.8 in the main pom.xm and now >>>>> the generated .class have major.verion=52. >>>>> Unfortunately now I get this error: >>>>> >>>>> [ERROR] >>>>> /opt/flink-src/flink-java/src/main/java/org/apache/flink/api/java/typeutils/runtime/TupleSerializer.java:[104,63] >>>>> incompatible types: void cannot be converted to java.lang.Object >>>>> >>>>> How can I fix it? I also tried to upgrade the maven compiler to 3.5 but >>>>> it didn't help :( >>>>> >>>>> Best, >>>>> Flavio >>>>> >>>>> On Wed, Feb 3, 2016 at 2:38 PM, Flavio Pompermaier >>>>> <pomperma...@okkam.it> wrote: >>>>>> >>>>>> Hi to all, >>>>>> >>>>>> I was trying to make my Java 8 application to run on a Flink 0.10.1 >>>>>> cluster. >>>>>> I've compiled both Flink sources and my app with the same Java version >>>>>> (1.8.72) and I've set the env.java.home to point to my java 8 JVM in >>>>>> every >>>>>> flink-conf.yml of the cluster. >>>>>> >>>>>> I always get the following Exception: >>>>>> >>>>>> java.lang.UnsupportedClassVersionError: XXX: Unsupported major.minor >>>>>> version 52.0 >>>>>> >>>>>> Is there any other setting I forgot to check? Do I have to change also >>>>>> the source and target to 1.8 in the maven compiler settings of the main >>>>>> pom? >>>>>> >>>>>> Best, >>>>>> Flavio >>>>> >>>>> >>>>> >>>> >> > >
