name: lombok-patterns
description: Lombok annotations and best practices for Java 21+ projects. Use when reducing boilerplate, configuring builders, or choosing between Lombok and Records.

Lombok Patterns

This skill provides guidance on using Project Lombok to reduce boilerplate code in Java applications, covering annotations, best practices, and integration patterns.

Note: This guide targets Java 21+ projects. Some Lombok features are now obsolete due to modern Java features (Records, var, try-with-resources). See Java 21+ Considerations below.

Overview

Lombok is a Java library that automatically generates common code like getters, setters, constructors, builders, and more during compilation. It helps create cleaner, more maintainable code.

Java 21+ Considerations

Some Lombok features are now redundant with modern Java:

When Lombok Still Adds Value

• JPA Entities: Records don't work with JPA (need no-arg constructor, mutable state)
• @Builder: Records don't have built-in builder support
• @Slf4j: No Java equivalent for logger generation
• @RequiredArgsConstructor: Useful for Spring dependency injection
• Inheritance: Records can't extend classes

Annotation Categories

Core Annotations (Still Valuable)

Consider Java Records Instead

// ✅ Prefer Java Record for simple value objects
public record Money(BigDecimal amount, String currency) {}

// ✅ Prefer Java Record for simple DTOs
public record CustomerDTO(String name, String email) {}

// ✅ Use Lombok for JPA entities (records don't work with JPA)
@Entity
@Getter
@Setter
@NoArgsConstructor
public class Customer {
    @Id private Long id;
    private String name;
}

Logging Annotations

Field & Method Annotations

Quick Reference

JPA Entities (Lombok Recommended)

@Entity
@Getter
@Setter
@NoArgsConstructor
@AllArgsConstructor
@EqualsAndHashCode(onlyExplicitlyIncluded = true)
public class Product {
    @Id
    @EqualsAndHashCode.Include
    private Long id;

    private String name;
    private BigDecimal price;
}

Spring Services

@Service
@RequiredArgsConstructor
@Slf4j
public class OrderService {
    private final OrderRepository orderRepository;
    private final PaymentService paymentService;

    public Order process(Order order) {
        log.info("Processing order: {}", order.getId());
        return orderRepository.save(order);
    }
}

Builder Pattern (Lombok Adds Value)

// Records don't have builder support - use Lombok
@Builder
public record Email(
    String to,
    String subject,
    String body,
    @Singular List<String> attachments
) {}

// Usage
Email email = Email.builder()
    .to("[email protected]")
    .subject("Hello")
    .body("Content")
    .attachment("file1.pdf")
    .build();

Best Practices

✅ Do

• Use Java Records for simple value objects and DTOs
• Use @RequiredArgsConstructor with final fields for dependency injection
• Use @Slf4j for logging instead of manual logger creation
• Use @Builder for classes with many optional fields
• Be explicit with @EqualsAndHashCode on JPA entities

❌ Avoid

• Using @Data or @Value when a Java Record would suffice
• Using @Data on JPA entities (use individual annotations)
• Using @EqualsAndHashCode with lazy-loaded JPA relationships
• Overusing @SneakyThrows (makes exception handling unclear)

Common Pitfalls

Cookbook Index

Core Annotations

• data-annotation - @Data (consider Records instead)
• value-annotation - @Value (consider Records instead)
• getter-setter - @Getter and @Setter
• constructor-annotations - Constructor generation
• builder-annotation - Builder pattern with @Builder
• logging-annotations - Logger generation

Field & Method Annotations

• non-null - Null checking with @NonNull
• with-annotation - Immutable setters with @With
• sneaky-throws - Checked exception handling
• synchronized-annotation - Thread safety

Integration Patterns

• entity-patterns - JPA/Hibernate best practices
• equals-hashcode-jpa - Entity identity
• dependency-injection - Spring constructor injection
• configuration-properties - Spring Boot configuration