How do I support the crippling diversity of RNGs in the Java/Scala Ecosystem?

[jbn]

What is the proper default? Are implicit wrapping conversions too expensive?

[jbn]

General Solution

scala.util.Random wraps a java.util.Random. So, it delegates to any class that extends java.util.Random. An implicit conversion can unwrap it with negligible cost. Commons Math3 has a RandomAdapter that extends java.util.Random. Thus, it conforms with scala.util.Random. An additional implicit conversion to a RandomGenerator lets a RandomAdapter-wrapping scala.util.Random work with Commons Math3.

This feels like a damn ugly solution, but it has its pluses. For one, it is unobtrusive to Scala developers. They expect scala.util.Random. And, it works seemlessly with libraries that expect a java.util.Random. Finally, it provide a general pattern for interoperability with libraries that roll their own RNG hierarchies.

For (rough) performance considerations, see: https://github.com/generativists/ImplicitRNGPerfTest