I had cause to use a bit of Java recently, so I could wrap an existing library that did exactly the thing I wanted. I haven't used it since university—back in the 1.4 days—and I was actually pleasantly surprised. Performance was great, concurrency was easy, features like type inference and streams made the experience much more pleasant, and obviously the development tools are still first-rate.

The absence of a package manager like Bundler or Cargo was frustrating for someone coming from that environment – as was the effective requirement to use an IDE. But on the whole, the platform feels like something that totally-hip-and-edgy-clique developers like myself are too quick to discount.