PARQUET-1590: Add Java 11 to Travis

[Fokko]

https://jira.apache.org/jira/browse/PARQUET-1499
https://jira.apache.org/jira/browse/PARQUET-1590

Depends on #133

[zivanfi]

Apparently Gradle 4.4.1 does not support Java 11: https://stackoverflow.com/questions/54358107/gradle-could-not-determine-java-version-from-11-0-2

[Fokko]

I'm surprised as well. Thrift is still using Gradle 4.x, while master is at 5.x.

[zivanfi]

Travis:

./gradlew wrapper --gradle-version 5.1.1
Downloading https://services.gradle.org/distributions/gradle-4.4.1-bin.zip

That's... interesting...

[Fokko]

Was trying to come up with a workaround, until Thrift 0.13 will be released :-) In the end, right now we're building Thrift 0.12 from scratch, but it should preferred to pull in the binaries instead.

[zivanfi]

I'm officially confused:

zi@kermit:/tmp (0)$ ./gradlew wrapper --gradle-version 5.1.1
Downloading https://services.gradle.org/distributions/gradle-4.4.1-bin.zip

zi@kermit:/tmp (0)$ ./gradlew wrapper --distributionUrl=https\://services.gradle.org/distributions/gradle-5.4.1-bin.zip
Downloading https://services.gradle.org/distributions/gradle-5.1.1-bin.zip

Since the --gradle-version parameter seemed to have no effect, I have tried the --distributionUrl parameter using an example from the Gradle docs. I requested version 5.4.1 and got 5.1.1... But why?

[Fokko]

That feels weird indeed. I think the explanation is somewhere here: https://docs.gradle.org/current/userguide/gradle_wrapper.html#customizing_wrapper

With the configuration in place running ./gradlew wrapper --gradle-version 5.4.1 is enough to produce a distributionUrl value in the Wrapper properties file that will request the -all distribution.

I think the distributionUrl is being overridden by the earlier -gradle-version 5.1.1.

[zivanfi]

It just keeps getting better and better:

zi@kermit:/tmp (0)$ rm -r ~/.gradle
zi@kermit:/tmp (0)$ ./gradlew wrapper --gradle-version 5.4.1
Downloading https://services.gradle.org/distributions/gradle-5.4.1-bin.zip
zi@kermit:/tmp (0)$ rm -r ~/.gradle
zi@kermit:/tmp (0)$ ./gradlew wrapper --gradle-version 5.1.1
Downloading https://services.gradle.org/distributions/gradle-5.4.1-bin.zip

[zivanfi]

I think I solved the mystery. From a clean state:

zi@kermit:/tmp (0)$ ./gradlew wrapper --gradle-version 5.1.1
Downloading https://services.gradle.org/distributions/gradle-4.4.1-bin.zip
zi@kermit:/tmp (0)$ ./gradlew wrapper --gradle-version 5.1.1
Downloading https://services.gradle.org/distributions/gradle-5.1.1-bin.zip
zi@kermit:/tmp (0)$ ./gradlew wrapper --gradle-version 5.4.1
# Nothing downloaded
zi@kermit:/tmp (0)$ ./gradlew wrapper --gradle-version 5.4.1
Downloading https://services.gradle.org/distributions/gradle-5.4.1-bin.zip

It seems to me that these options only have an effect of the next command, but not the current one. They set the URL that is located in the ./wrapper/gradle-wrapper.properties file, but only after the gradle wrapper has already read them, therefore it will keep using the old values until restarted.

[Fokko]

@zivanfi This makes perfect sense. Also in the CI, we see that it first runs the current version, and then it tries to upgrade/set the new version.

[zivanfi]

Do you see any way to make this work?

[Fokko]

Yes, I found a way. We don't need to compile the Java stuff actually, because maven will just pull this from maven central. Therefore we don't need gradle :-)