Lambda Expressions In Java

In Java, a Lambda expression is like a shortcut for creating a small piece of code that does something specific. It's especially useful when you only need a quick function and don't want to write a whole method.

Imagine you have something called a "functional interface," which is just a special kind of interface in Java that has only one job to do. We call it "functional" because it's designed to perform a specific function.

Now, instead of writing a regular method and going through the whole process, Java 8 introduced Lambda expressions to make things quicker. It's a way to write a brief piece of code that takes some input, does something with it, and gives you a result.

• (String name) -> { return "Hi"+name } Lambda Expression

• This function takes one input parameter does some operations with it and returns the result.

A Sample Code With Explanation

• It is an interface which has an abstract method to find the area of a rectangle.

public interface Rectangle {
void areaOfARectangle(int length, int width);
}

• Main Function
  public class LambdaExpressionExamples {

  public static void main(String arg[]) {
  //Without Using Lambda

  Rectangle rectangle = new Rectangle() {
      @Override
      public void areaOfARectangle(int length, int width) {
          System.out.print("Area Of A Rectangle: "+length * 
                           width);
      }
  };
  
  rectangle.areaOfARectangle(5, 10);
  
  //With Lambda
  
  Rectangle rectangle1 = (int length, int width) -> {
      System.out.print("Area Of An Rectangle: "+length * 
                       width);
  };
  
  rectangle1.areaOfARectangle(10, 4);
  

  }
  }