# Lambda Expression

A compact function-like value that implements a functional interface.

## What is **Lambda Expression** in Java?

**Lambda Expression** — A compact function-like value that implements a functional interface.

```java
import java.util.function.Function;

class LabelFormatter {
    Function<String, String> uppercase = String::toUpperCase;
}
```

Level: Freelancer · [More Java terms at this level](https://www.ask-codey.com/glossary/subjects/java/freelancer)

Updated: September 27, 2026

## In other subjects

- [Lambda Expression in C#](https://www.ask-codey.com/glossary/lambda-expression-c-sharp)

Source: https://www.ask-codey.com/glossary/lambda-expression