--- title: "Project Lombok" url: "https://www.bekk.christmas/post/2019/07/project-lombok" authors: ["Nicklas Utgaard"] published: "2019-12-07" updated: "2024-11-07T13:05:28Z" language: "en-US" type: "article" tags: ["Java"] --- # Project Lombok Want to use the `var` keyword, but your team is stuck on Java 8? Lombok can help you. Sick and tired of writing and maintaining getters and setters? Lombok can help you. ## In short Project Lombok adds compile-time annotations and keywords that reduce Java boilerplate, including getter/setter generation, builders, logging, and concise local variable declarations like val. It can make older Java codebases feel closer to newer Java features, but it relies on IDE support and internal or non-standard APIs. - **For:** Java developers working in older codebases - **Good to know beforehand:** Basic Java knowledge _AI-generated_ [Project Lombok](https://projectlombok.org) is a Java compile-time library that “extends” the Java-experience by adding new and exciting annotations and keywords. It does this by utilizing [JSR 269: Pluggable Annotation Processing API](https://www.jcp.org/en/jsr/detail?id=269) and a myriad of other internal and/or compiler-specific APIs. ## Peeking into the future While some projects may be using Java 11 or 13, there is still a lot of developers and code stuck in the pre- Java-9 era. Project Lombok might help you to peek into the future if this is your everyday reality. Java 10 introduces the `var` keyword, extending the usage of type inference to include your everyday variables. In term of code this means that the previously verbose `Customer customer = new Customer("Frank");`, can be simplified to `var customer = new Customer("Frank");`. Add Project Lombok to your built tool and you may experience this glorious new-found freedom yourself, even if you're stuck at Java 8. As a treat, Project Lombok even adds `val`, which is similar to Java 10's `final var`. ## So much code, yet no value Writing and maintaining a decent sized domain-object can be extremely tedious. Update a field name, and you better make sure you update your getters and setters. Perhaps your team likes using the [builder-pattern](https://en.wikipedia.org/wiki/Builder_pattern), adding even more required maintenance. Project Lombok's remedy; add `@Getter`, `@Setter` and `@Builder` to you domain class, and you're good. Project Lombok introduces a [whole set of interesting annotations](https://projectlombok.org/features/all) to use. Some of the ones I've used the most are: - `@Data` - Shortcut for `@Getter`, `@Setter`, `@ToString`, `@EqualsAndHashCode`, and `@RequiredArgsConstructor`. - `@Value` - Immutable variant of `@Data` - `@Slf4j` - Adds `private static final Logger log` - `@ToString` - Generates a human-readable `toString` method - `@EqualsAndHashCode` - Generates `hashCode` and `equals` based on the fields in your object ## Not all roses and sunshine While Project Lombok undoubtedly has some nice features, it also comes with a cost and risks. - In order for your team to be productive they must all install an IDE plugin. Most major IDEs are supported. - The usage of non-standard/internal APIs, and how this may affect the future of the codebase. Other alternatives may also be better suited for your team, e.g; upgrading to a newer version of Java, or introducing Kotlin if you main concern is reducing boilerplate code. ## Relevant resources recommended by the author - [Project Lombok homepage](https://projectlombok.org) - [JSR 269: Pluggable Annotation Processing API](https://www.jcp.org/en/jsr/detail?id=269) - [Builder pattern](https://en.wikipedia.org/wiki/Builder_pattern) - [Lombok features](https://projectlombok.org/features/all)