They are the two-argument counterparts of Function, Predicate, and Consumer: BiFunction takes two arguments and returns a result, BiPredicate takes two arguments and returns a boolean, and BiConsumer takes two arguments and returns nothing. A common use is Map.forEach(BiConsumer ), which receives both the key and value of each entry.

beginnerFunctional Programming

What are the BiFunction, BiPredicate, and BiConsumer functional interfaces?

They are the two-argument counterparts of Function, Predicate, and Consumer: BiFunction<T, U, R> takes two arguments and returns a result, BiPredicate<T, U> takes two arguments and returns a boolean, and BiConsumer<T, U> takes two arguments and returns nothing. A common use is Map.forEach(BiConsumer<K, V>), which receives both the key and value of each entry.

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