This week's book giveaway is in the Reactive Progamming forum. We're giving away four copies of Reactive Streams in Java: Concurrency with RxJava, Reactor, and Akka Streams and have Adam Davis on-line! See this thread for details.
Actually, from your description I came up with something like this:
Although, I don't understand "passing argument to this interface", do you mean passing argument to method of used functional interface / object of given functional interface ?
Because, if this is the case, then those are 2 different cases. In first one, you are actually also calling for execution and providing actual argument of functional interface function, whereas in second example you only define behavior, but have not power over actual argument or execution.
If you meant by that description scenario like this:
Then I guess it depends on reusability of that function. Same as some Strings in class, if you use them on multiple places, define it as field/constant in class otherwise second approach is more suitable.
I think I'll just lie down here for a second. And ponder this tiny ad:
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