I don't really feel that Java uses proven features.
For example they used checked exceptions. Those definitely do not seem like proven feature. C++ has unchecked exceptions. Almost every other popular language has unchecked exceptions. Java went with checked exceptions and nowadays they are almost universally ignored by developers. I'd say that's a total failure.
Streams another good example. Making functional API for collections is pretty trivial. But they decided to design streams for some kind of very easy parallelisation. This led to extremely complicated implementation, absurdly complicated. And I've yet to encounter a single use-case for this feature. So for very rare feature they complicated the design immensely.
Modules... LoL.
We will see how green threads will work. Most languages adopt much simpler async/await approach. Very few languages implement green threads.
For example they used checked exceptions. Those definitely do not seem like proven feature. C++ has unchecked exceptions. Almost every other popular language has unchecked exceptions. Java went with checked exceptions and nowadays they are almost universally ignored by developers. I'd say that's a total failure.
Streams another good example. Making functional API for collections is pretty trivial. But they decided to design streams for some kind of very easy parallelisation. This led to extremely complicated implementation, absurdly complicated. And I've yet to encounter a single use-case for this feature. So for very rare feature they complicated the design immensely.
Modules... LoL.
We will see how green threads will work. Most languages adopt much simpler async/await approach. Very few languages implement green threads.