DZone
Thanks for visiting DZone today,
Edit Profile
  • Manage Email Subscriptions
  • How to Post to DZone
  • Article Submission Guidelines
Sign Out View Profile
  • Post an Article
  • Manage My Drafts
Over 2 million developers have joined DZone.
Log In / Join
Refcards Trend Reports Events Over 2 million developers have joined DZone. Join Today! Thanks for visiting DZone today,
Edit Profile Manage Email Subscriptions Moderation Admin Console How to Post to DZone Article Submission Guidelines
View Profile
Sign Out
Refcards
Trend Reports
Events
Zones
Culture and Methodologies Agile Career Development Methodologies Team Management
Data Engineering AI/ML Big Data Data Databases IoT
Software Design and Architecture Cloud Architecture Containers Integration Microservices Performance Security
Coding Frameworks Java JavaScript Languages Tools
Testing, Deployment, and Maintenance Deployment DevOps and CI/CD Maintenance Monitoring and Observability Testing, Tools, and Frameworks
Partner Zones AWS Cloud
by AWS Developer Relations
Culture and Methodologies
Agile Career Development Methodologies Team Management
Data Engineering
AI/ML Big Data Data Databases IoT
Software Design and Architecture
Cloud Architecture Containers Integration Microservices Performance Security
Coding
Frameworks Java JavaScript Languages Tools
Testing, Deployment, and Maintenance
Deployment DevOps and CI/CD Maintenance Monitoring and Observability Testing, Tools, and Frameworks
Partner Zones
AWS Cloud
by AWS Developer Relations
The Latest "Software Integration: The Intersection of APIs, Microservices, and Cloud-Based Systems" Trend Report
Get the report

5 Tips For Using Lombok In Production

This look at using Lombok to reduce boilerplate code in production examines useful annotations and a few general practices to keep in mind.

Alex Collins user avatar by
Alex Collins
·
Jun. 01, 17 · Tutorial
Like (20)
Save
Tweet
Share
43.72K Views

Join the DZone community and get the full member experience.

Join For Free

I was reminded the other day about the excellent Project Lombok. If you're not familiar with this tool, it helps reduce boilerplate AND testing. You annotate your Java source code with some special annotations, and it generates code for you. For example, if you annotate a field with a @Getter, it generates a public getter method for that field.

Having previously used it successfully on a number of production systems, here are my top five tips.

Tip 1: No Lombok With Logic

Bytecode compiled for generated code is hard to debug. This is made more confusing where generated code gets mixed with logic. Lombok works well if you don't mix it with logic.

A useful side effect of this tip is that classes only contain generated code.

Tip 2: Don't Test the Generated Code

The generated code is trustworthy, so you can save a lot of time by not testing it or performing static analysis on it.

If a class only contains fields, then you don't need to test it or perform static analysis on it.

Tip 3: Use @Data for Your DAOs

Where is Lombok especially useful then? In DAOs. These objects typically don't have a lot of logic and carry a great deal of boilerplate. Specifically, three annotations were the most useful, two of which we'll get to in the next sections.

@Data creates your getters, setters, to string, and equals/hashcode. Great for DAOs in either the database layer or the API layer.

Tip 4: Use @Value for Immutable Value Objects

@Value is essentially an immutable version of @Data. Very useful for immutable value objects. Use in many of the cases you might use a Scala case class.

Tip 5: Use @Builder

@Builder is useful when you have an object with many fields with the same type. Rather than having a constructor with many string fields, use the builder instead.

Tip 6: Think About Avoiding the Other Annotations

There are a number of annotations that we never found widely useful:

  • val: A great idea, but hobbled by poor IDE support.
  • @Cleanup: Use try-with-resources.
  • @SneakyThrows: Throw only runtime exceptions, and perform exception mapping where needed.
  • @Synchronized: Just never found a place to use this.

Tip 7: Exclude Generated Classes From Sonar Reports

As the generated code typically ends up with many untested methods (e.g. you never test the generated equals, as you don't need to, but they tend to end up being very complex for classes with many fields), these classes are excluded for static analysis and code coverage. If you are using Maven and Sonar, you can do this using the sonar.exclusions property.

Production (computer science)

Opinions expressed by DZone contributors are their own.

Popular on DZone

  • 5 Recent Amazing AI Advancements
  • Web Testing Tutorial: Comprehensive Guide With Best Practices
  • How to Assess the Technical Skills of a Software Development Partner
  • Effective Jira Test Management

Comments

Partner Resources

X

ABOUT US

  • About DZone
  • Send feedback
  • Careers
  • Sitemap

ADVERTISE

  • Advertise with DZone

CONTRIBUTE ON DZONE

  • Article Submission Guidelines
  • Become a Contributor
  • Visit the Writers' Zone

LEGAL

  • Terms of Service
  • Privacy Policy

CONTACT US

  • 600 Park Offices Drive
  • Suite 300
  • Durham, NC 27709
  • support@dzone.com
  • +1 (919) 678-0300

Let's be friends: