Remove/Update threetenbp dependency

[wing328]

Description

Please refer to #3251 (comment) for more information.

openapi-generator version

Latest master

Suggest a fix/enhancement

Remove the dependency from pom.xml

[cbornet]

More globally, that would mean support only JDK8+ generation.
Personally I wouldn't mind, we could do a big cleanup by not supporting older JDKs. The only reserve I have is regarding Android support.

[jimschubert]

Someone familiar with Android development could evaluate using the Java 8 features available in Android Studio. https://developer.android.com/studio/write/java8-support

[cbornet]

The probleme is that the java.time package is only available from API 26 and that represents less than 40% of the Android device distribution

[cbornet]

What could be removed at least is the supportJava6 option which only represents 3.8% of the distribution of android. And of course, any Android dev should consider moving to Kotlin but I don't know what share of the apps is now written in Kotlin.

[jimschubert]

Then maybe upgrading the dependency and documenting this as a known issue would be sufficient?

The timezone database embedded in our dependency is from 2015. The artifact's age is probably what triggered the message. But, if people are relying on our code in any way for accurate jsr310 time representations, there are going to be a lot of edge cases that aren't covered due to its age.

[cbornet]

It's weird: from what I see most of our builds use threetenbp v1.3.5 which depends on TZDB 2017b

[cbornet]

We could upgrade threeten to the latest version btw

[UkonnRa]

For me, I don't like using threeten as default. Because it is not a famous or the standard lib. I strongly recommand using java8 as the default one

[wing328]

@UkonnRa good suggestion. Can you please file a PR against 5.1.0 branch to the default value of dateLibrary?

[UkonnRa]

@UkonnRa good suggestion. Can you please file a PR against 5.1.0 branch to the default value of dateLibrary?

Hi I am glad to do this, but for I am not familiar with the project and I have no idea how to fix this, maybe letting the experts fix this is a quicker and safer solution I think :-)