lambda and MethodHandles in current prototype

[Maurizio Cimadamore]

On 20/11/11 19:58, Peter Levart wrote:
> Has the compilation strategy changed? Aren't MethodHandles used any more or are they still, but the conversion to functional interfaces doesn't use MethodHandleProxies.asInterfaceInstance()? Are there any plans for the above code to print true/true (or at least false/true)?
Yes, the implementation has changed - the compiler used 
MethodHandleProxies.asInterfaceInstance for translating method 
references - a couple of weeks ago I cleaned up the compiler to support 
two different (and consistent) translation strategies:

*) by default, the compiler will generate anonymous inner class for 
lambdas/method references

*) optionally (if you use the -XDlambdaToMethod flag), the compiler will 
use 292, by passing method handles on to a fake BSM lambda metafactory 
that will spin the bytecode on the fly.

So, the conclusion is that the compiler doesn't use 
MethodHandleProxies.asInterfaceInstance directly anymore - either it 
just emit an anonymous inner class, or it defers creation to a BSM which 
then could, in principle, use MethodHandleProxies.asInterfaceInstance or 
do some other fancy stuff to spin bytecode on the fly.

Maurizio