There was an interesting discussion about Java recently. It does not directly address your question, but nonetheless, there were some interesting perspectives discussed.
I thought it might be interesting for you to see Java put into context with other languages (among which is Kotlin), in case you missed it:
If you love Java, not really. Kotlin may end up becoming one of the more popular languages. But, Java companies are not likely to stop using Java. If you do not like Java like me, you might find you love Kotlin.