What are first-class functions in Java?

What are first-class functions in Java?

First-class functions are functions that can be treated like any other variable. In Java, this concept is implemented using functional interfaces and lambda expressions.

Can you give me an example of a first-class function in Java?

Sure! Here's a simple example using a functional interface:

@FunctionalInterface
interface MyFunction {
    int apply(int x);
}

public class Main {
    public static void main(String[] args) {
        MyFunction square = (x) -> x * x;
        System.out.println(square.apply(5)); // Outputs 25
    }
}

How do first-class functions improve code in Java?

They enhance code readability and reusability, allowing for cleaner and more modular code through higher-order functions.

Are there any limitations to using first-class functions in Java?

Yes, while Java supports first-class functions, it is still statically typed, which can limit some dynamic behaviors found in other languages.