IntFunction Interface in Java with Examples Last Updated : 08 Oct, 2018 Comments Improve Suggest changes Like Article Like Report The IntFunction Interface is a part of the java.util.function package which has been introduced since Java 8, to implement functional programming in Java. It represents a function which takes in an int-valued argument and produces a result of type R. This functional interface takes in only one generic, namely:- R: denotes the type of the output of this function The lambda expression assigned to an object of IntFunction type is used to define its apply() which eventually applies the given operation on its only argument. It is similar to using an object of type Function<Integer, R>. The IntFunction interface has only one function: apply() This method accepts an int-valued argument and gives a result of type R. Syntax: R apply(int value) Parameters: This method takes in one parameter value which is an int-valued argument. Returns: This method returns a value of type R. Below is the code to illustrate apply() method: Program Java import java.util.function.IntFunction; public class Main { public static void main(String args[]) { IntFunction<Double> ob = a -> a / 2.0; // Using apply() method System.out.println(ob.apply(3)); } } Output: 1.5 Comment More infoAdvertise with us Next Article IntFunction Interface in Java with Examples P psil123 Follow Improve Article Tags : Misc Java Java - util package java-basics java-interfaces Java 8 +2 More Practice Tags : JavaMisc Similar Reads Java 8 | IntToLongFunction Interface in Java with Examples The IntToLongFunction Interface is a part of the java.util.function package which has been introduced since Java 8, to implement functional programming in Java. It represents a function which takes in an int-valued argument and gives a long-valued result. The lambda expression assigned to an object 1 min read ToIntFunction Interface in Java with Examples The ToIntFunction Interface is a part of the java.util.function package which has been introduced since Java 8, to implement functional programming in Java. It represents a function which takes in an argument of type T and produces an int-valued result. This functional interface takes in only one ge 1 min read Java 8 | IntToDoubleFunction Interface in Java with Examples The IntToDoubleFunction Interface is a part of the java.util.function package which has been introduced since Java 8, to implement functional programming in Java. It represents a function which takes in an int-valued argument and gives a double-valued result. The lambda expression assigned to an obj 1 min read ToIntBiFunction Interface in Java with Examples The ToIntBiFunction Interface is a part of the java.util.function package which has been introduced since Java 8, to implement functional programming in Java. It represents a function which takes in two arguments of type T and U and produces an int-valued result. This functional interface takes in t 2 min read LongToIntFunction Interface in Java with Examples The LongToIntFunction Interface is a part of the java.util.function package which has been introduced since Java 8, to implement functional programming in Java. It represents a function which takes in a long-valued argument and gives an int-valued result. The lambda expression assigned to an object 1 min read Like