How stable is the lamba translation? If this changes or is different for different JVMs, will that break things? Bryan
On Wed, May 28, 2014 at 8:29 AM, Peter <j...@zeus.net.au> wrote: > So far, a subset of Lambda's appear very suitable for marshalling > remotely, where their code can execute in a remote jvm. > > A lambda, that doesn't refer to object methods in its enclosing class, > results in the java compiller creating a static method that accepts > captured object arguments, containing the lambda's block code. > > With ASM, I can very easily read a class and strip out all but this static > method. A non instantiable class file with no class init. > > This class can be given a temporary known name, unrelated to the original > client code (not intended for class loading, but identity). > > A named identity of this class can then be created using a message digest > of the class bytes. > > The class byte code can be packaged and serialized remotely. > > Upon deserialization, the class can be rewritten again (if not loaded > previously) and named after its message digest, and given a new object > method to implement the functional interface, final fields added to hold > serialized captured arguments, and a constructor that accepts the captured > arguments. > > It is now a simple basic object that calls a static method with arguments. > > The class file would be verified, then loaded into a ClassLoader with no > permissions. > > The class would be cached in a Map with weak values, the key being the > message digest, so idential deserialized lambda's wouldn't need to rewrite > and load their class bytecode. > > These lambda's could be used in services to allow remote internal > iteration, over large data collections, like distributed hash tables, to > process and return results. > > An argument captured by a lambda, could itself be a remote service, used > as a callback. Lambda's could be stored by services, and used like queries > to notify remote listeners of changes in service state. > > A bit like an Event notification version of Map Reduce. > > It seems reasonable that distributed lambda's should provide a subset of > Java lambda expressions based on static compilled methods and that all > object arguments that lambda's capture should be or implement public api or > service api. > > Thoughts? > > Peter.
