Java lambda expressions are a feature introduced in Java 8 that provide a concise way to represent functional interfaces (interfaces with a single abstract method) using an expression instead of a full class implementation. Essentially, lambdas allow you to pass behavior (i.e., a block of code) as an argument to methods, providing more readable, less verbose code.
Syntax of Lambda Expressions:
(parameter1, parameter2, …) -> expression or block of code
Example:
// Lambda expression to add two numbers
BinaryOperator add = (a, b) -> a + b;
System.out.println(add.apply(3, 4)); // Output: 7
Key Features:
- Concise: They reduce the verbosity of code by eliminating boilerplate code, especially for simple functional interface implementations.
- Functional Programming: Lambda expressions make it easier to work with functional-style programming paradigms (like passing behavior as arguments).
- Improved readability: The syntax is compact, making the code easier to understand.
When to Use Lambda Expressions:
- For Functional Interfaces: Use lambdas when you’re working with functional interfaces (those that have exactly one abstract method). Common examples include
Runnable,Callable,Comparator, and various interfaces injava.util.functionlikePredicate,Function, etc.Example withRunnable:
