DKPro Similarity is definitely still maintained and supported.
One difference is that due to the many, many third party libraries
used in the project, similarity is not yet on maven central.
This can cause some problems if you have not added the additional
repositories in your settings.xml as described here:
If you experience any other problems, I am sure that we can figure out
what is going on.
Unfortunately, I don't know any other alternatives that provide the
functionality that you are looking for.
>> > email to dkpro-similarity-...@googlegroups.com
> You received this message because you are subscribed to the Google Groups
> "dkpro-core-user" group.
> To unsubscribe from this group and stop receiving emails from it, send an
> email to dkpro-core-us...@googlegroups.com