Lambda Expressions
Method vs Lambda
Method is always belongs to any class or object.
Lambda expressions does not belong to any class or object.
Method has — name, parameter list, body, return type.
Lambda expression
A lambda expression is a short block of code that takes in parameters and returns a value, used to implement the single abstract method of a functional interface. It enables you to treat functionality as a method argument or assign it to a variable.
It is an anonymous function so no need to have a name. A lambda expression in Java is a concise way to represent an anonymous function — that is, a method without a name that you can pass around as a value.
It has a parameter list and method body. [body can have single or multiple statements]
No need to have a return type. Java 8 compiler can infer the return type.
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Lambda expression syntax
This function take two integer parameters and returns the sum.
🔹 Why Use Anonymous Functions?
An anonymous function is a function without a name. You define it inline, often to pass as an argument to another method or to assign to a variable.
In Java, lambda expressions are anonymous functions.
1. Concise code
No need to create a full method or class for small logic.
2. Functional programming
Lets you treat behavior as data, pass functions around.
3. Readability + Reusability
Useful for one-time use logic like filtering, sorting, etc.
An anonymous function is a nameless function used to define behavior inline. In Java, it’s implemented using lambda expressions and is useful for passing behavior to methods like filter(), sort(), or map() — leading to cleaner, shorter, and more expressive code.
Implementing Functional interfaces method through lambda expressions
