What is the IntFunction functional interface in Java?
IntFunction is a functional interface in Java that accepts one argument of type int and returns a result R. The interface contains one method, i.e., apply.
The IntFunction interface is defined in the java.util.function package. To import the IntFunction interface, check the following import statement.
import java.util.function.IntFunction;
Method
The apply(int value) method applies the function to the given argument of type int. This is the functional method of the interface.
Syntax
R apply(int value);
Parameter
int value: The function argument of typeint.
Returns
R: The method returns the function result.
Code
import java.util.function.IntFunction;public class Main{public static void main(String[] args) {IntFunction<String> stringIntFunction = (d) -> String.format("The passed value is %s", d);int i = 100;// calling apply method of the IntFunctionSystem.out.println(stringIntFunction.apply(i));}}
In the above code, we created an implementation of the IntFunction interface that accepts an int argument and returns a string.