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 two generics, namely:-

• T: denotes the type of the first input argument to the operation
• U: denotes the type of the second input argument to the operation

The lambda expression assigned to an object of ToIntBiFunction type is used to define its applyAsInt() which eventually applies the given operation on its two arguments. It is similar to using an object of type BiFunction<T, U, Integer>.

The ToIntBiFunction interface has only one function:

applyAsInt()

This method accepts two arguments of type T and U and produces an int-valued result.

Syntax:

int applyAsInt(T t, U u)

Parameters: This method takes in two parameters:

• t– the first input argument
• u– the second input argument

Returns: This method returns an int-valued result.

Below is the code to illustrate applyAsInt() method:

Program

import java.util.function.ToIntBiFunction;

public class Main {
    public static void main(String args[])
    {

        ToIntBiFunction<Integer, String>
            ob = (a, b) -> a + Integer.parseInt(b) * 3;

        // Using applyAsInt() method
        System.out.println(ob.applyAsInt(3, "10"));
    }
}

Output:

33