What are some examples of Java lambda expressions?

What are some examples of Java lambda expressions?

Java lambda expressions are a way to provide clear and concise syntax for writing anonymous methods. Here are a few examples:

1. Basic Example:

   (a, b) -> a + b
   

   This represents a function that takes two parameters and returns their sum.

2. Using with Collections:

   List<String> names = Arrays.asList("Alice", "Bob", "Charlie");
   names.forEach(name -> System.out.println(name));
   

   This prints each name in the list.

3. Filtering a List:

   List<Integer> numbers = Arrays.asList(1, 2, 3, 4, 5);
   List<Integer> evenNumbers = numbers.stream().filter(n -> n % 2 == 0).collect(Collectors.toList());
   

   This filters out even numbers from the list.

Can you explain the syntax of a lambda expression?

Sure! The syntax of a lambda expression consists of three parts:

1. Parameters: The input parameters are enclosed in parentheses. For example, (x, y).
2. Arrow Token: The -> separates the parameters from the body of the expression.
3. Body: The body can be a single expression or a block of code. For example, x + y or { return x + y; }.

What are the benefits of using lambda expressions?

Lambda expressions provide several benefits:

1. Conciseness: They reduce boilerplate code, making your code cleaner and easier to read.
2. Readability: They allow you to express instances of single-method interfaces (functional interfaces) more clearly.
3. Parallel Processing: They enable easier parallel processing with streams, improving performance.

Can you give me a real-world application of lambda expressions?

Certainly! A real-world application of lambda expressions is in event handling in GUI applications. For example, in JavaFX, you can use lambda expressions to handle button clicks:

button.setOnAction(event -> System.out.println("Button clicked!"));

This makes the code more readable and concise.