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Java 8 - Functions - Higher Order Function

  • A Higher Order Function (HOF) is one whose input and/or output is a function.

public class HigherOrderFunction {

   static BiFunction<Function<Person, Person>, Person, String> inputOnlyHOF = (personFunction, p) -> personFunction.apply(p).getFirstName();

   static Function<Person, Function<Person, Person>> outputOnlyHOF = person -> ( p -> new Person(p.getFirstName()+person.getFirstName(), p.getLastName()+person.getLastName()) );

   public static void main(String[] args) {"inputOnlyHOF: " + inputOnlyHOF.apply(p -> new Person(p.getFirstName()+"s", p.getLastName()), new Person("Tom", "Cruise")) );"outputOnlyHOF: " + outputOnlyHOF .apply(new Person("Tom", "Cruise")) .apply(new Person("Ben", "Smith")) );



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