Grizzly 1.9.x vs Grizzly 2.3.x

Question

I have a Java application using Grizzly 1.9.59, Apparently around the version 1.5.x version 2.0 was also released with a totally new and incompatible API. Both versions are being developed 1.x being legacy.

So taking in consideration that both versions are being developed is it safe to assume they offer the same capabilities? What would be a really good reason to upgrade to 2.3.15(latest)?

Is there any documentation comparing both versions feature wise?

Does anyone know if they plan to stop developing 1.x, if so when?

Answer 1

I can't answer the question fully. But from their website:

The latest stable release of Grizzly is 2.3.14. Older versions of Grizzly (2.2.x, 1.9.x, 1.0.x) are still available and can be found on Maven Central.

So they see 1.9.x as an old version and on their website there are no direct download links, to 1.9.x. To me at least this indicates a wish to make uses adapt to the newest version.

So taking in consideration that both versions are being developed is it safe to assume they offer the same capabilities?

NO! It is not, many libraries run a legacy version, which primarily receives bug fixes and minor updates. File the new fancy version receives the awesome updates.

What would be a really good reason to upgrade to 2.3.15(latest)?

At some point when 1.xx no longer is developed you will have to do it anyways. But really it is a cost/benefit situation you are in

1. How much time will it take to do
2. Will you continued to use Grizzly
3. Is the new API, so hard to learn?
4. How much do I need to change the rest of my code

and so on, personally I would make the jump, if I where looking for a long term solution.

Is there any documentation comparing both versions feature wise?

I have not been able to find any, not even on there Jira

Does anyone know if they plan to stop developing 1.x, if so when?

Try their mailing list for answers to that, they properly no more and might be able to provide a feature table as well.

Summary: Their website focus on the newest version (and refer to prior as old versions), though 1.9.x still is in development. You can not be certain the two different versions has the same features and capabilities. If they stop developing 1.xx you would still need to update to the newest version.
For questions about more project specific things try their mailing list

A small note, your question is pretty open. I know my answer is more a comment but not enough space in the comments.