Hackforge Academy

Explanation

Slide 1: Introduction to Arrow Functions (Lambda Expressions) Arrow functions in Java are called Lambda Expressions, introduced in Java 8. They allow you to write shorter and cleaner code by representing anonymous functions.

Code:

(parameters) -> expression

Explanation

Slide 2: Why Use Lambda Expressions? They reduce boilerplate code, improve readability, and make code more functional and concise compared to traditional anonymous classes.

Code:

// Without Lambda
Runnable r = new Runnable() {
  public void run() {
    System.out.println("Hello");
  }
};

// With Lambda
Runnable r = () -> 
System.out.println("Hello");

Explanation

Slide 3: Syntax of Lambda Expression Lambda expressions consist of parameters, arrow (->), and body. They can have no parameters, single parameter, or multiple parameters.

Code:

() -> System.out.println("No params");
(x) -> x * x;
(a, b) -> a + b;

Explanation

Slide 4: Common Use Cases Used with functional interfaces, collections, and Stream API for operations like filtering, mapping, and iteration.

Code:

List<Integer> list = Arrays.asList(1,2,3,4);
list.forEach(n -> System.out.println(n));

Explanation

Slide 5: Benefits Lambda expressions improve performance, enable functional programming style, and make code easier to maintain and understand.

Code:

list.stream()
    .filter(n -> n > 2)
    .forEach(System.out::println);