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Java 8 - Functions - Function Types - Function

  • A Function acts on an input and returns an output.
  • A UnaryOperator is a function whose input and output are of the same type.
  • A BiFunction is a function which acts on two inputs and returns an output.
  • A BinaryOperator is a BiFunction whose input and output are of the same type.
  • BinaryOperator.minBy and BinaryOperator.maxBy return a BinaryOperator which calculate min and max values of two inputs.

public class Function_ {

   static Function<Integer, Integer> incrementFunction = input -> input+1;
   static UnaryOperator<Integer> incrementFunction_2 = input -> input+1;

   static BiFunction<String, Integer, String> biFunction = (a, b) -> a + b;
   static BinaryOperator<String> concatFunction = (a, b) -> a + b;

   static BinaryOperator<Integer> max = BinaryOperator.maxBy((a,b) -> a.compareTo(b));
   static BinaryOperator<Integer> min = BinaryOperator.minBy((a,b) -> a-b);

   public static void main(String[] args) {;;"one", 1));"one", "two"));,3).toString());,3).toString());



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