efficient compared to what? Previous Java: Yes. C++: Yes. C#: maybe not. Functional Programming Language X with 2 dozen language feature supporting it: Definite

efficient compared to what? Previous Java: Yes. C++: Yes. C#: maybe not. Functional Programming Language X with 2 dozen language feature supporting it: Definitely not. But this is the Java Enhancement Process, and within this language AND the fact that this is specification/documentation example, this is efficient.