java - Can I return an anonymous closure in JRuby when an interface is expected? -

per the docs, can pass block method expects interface, , block converted anonymous implementation of interface. it's pretty cool!

however, have ruby subclass of java class, has method that's supposed return implements interface.

// java public abstract class parent {   public myinterface getit(); }

# ruby class child < parent   def getit     # need return implementation of myinterface?   end end

i have tried making proc , lambda, neither of work. can add method parent (in java) forces automatic conversion

protected myinterface passthrough(myinterface mi) { return mi; }

and works:

def getit   passthrough {|thing|     puts thing.inspect   } end

this seems hacky though. oversight in how jruby works, or missing alternate solution?

yes - should able ... use to_java on proc/lambda :

class child < parent   def getit     lambda { |*args| puts args.inspect }.to_java(java::myinterface)   end end

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