Indeed, pure Java crypto libraries (Bouncy Castle) were really nice a few weeks ago. When other languages/frameworks are wrapping or calling openssl, it's a really nice feeling to have a common crypto algorithms implemented in your languge/platform. Same goes for image encoding/decoding, database access, lots of examples.

Plus, there's the benefit of (essentially) standard builds, project layout, dependency management, and deployment strategies (jar or war). A java developer can walk into a new job and be productive right away.