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Java 8 - Functions - Functional Interface

  • All Java functions implement the FunctionalInterface interface.
  • A functional interface must contain exactly one abstract method declaration, but any number of default and static methods.
  • The @FunctionalInterface annotation can be omitted when creating a functional interface.

public class FunctionalInterface_ {

   interface Dog {
     String bark(Person person);

   public static void main(String[] args) {
     Dog dog = person -> "Bark at " + person.getFirstName(); Person("Tom", "Smith")));



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