Choosing Between Java Records and Lombok @Data for Immutable Data Carriers

The Problem: Boilerplate vs. Immutability

When creating Data Transfer Objects (DTOs) or Value Objects, Java developers traditionally face a choice: write tedious boilerplate (getters, setters, equals(), hashCode(), and toString()) or use a tool to generate it. The goal is usually to create an immutable data carrier—an object whose state cannot change after construction—to ensure thread safety and prevent accidental state mutation.

The decision typically falls between using Java Records (introduced as a standard feature in JDK 16) and Lombok (a third-party library that generates bytecode via annotations). Choosing the wrong one can lead to compatibility issues with serialization frameworks or deployment hurdles due to JDK version constraints.

Comparison of Data Carrier Options

Feature	Java Records	Lombok @Data / @Value
Immutability	Enforced (final fields)	Mutable (@Data) or Immutable (@Value)
JDK Requirement	JDK 16+	JDK 8+
Dependencies	None (Native)	External library + IDE Plugin
Accessor Style	name()	getName()
Serialization	Native support; Jackson/Gson compatible	Compatible; requires config for @Value

Trade-offs and Constraints

Java Records: The Native Approach

Records are a language-level feature. They are not just a shorthand for classes; they are a distinct type designed specifically to hold data. Because the compiler handles the implementation, there is no risk of the generated code drifting from the field definitions.

• Pros: No external dependencies, faster compilation, and clear semantic intent.
• Cons: They cannot extend other classes (they implicitly extend java.lang.Record) and cannot have instance fields other than those defined in the record header.

Lombok: The Flexible Approach

Lombok uses an annotation processor to inject methods into the bytecode during compilation. While @Data provides a mutable JavaBean, @Value is the closer equivalent to a Record, marking all fields as private final.

• Pros: Works on legacy JDKs (8, 11) and allows for class inheritance.
• Cons: Requires every developer on the team to install an IDE plugin; can complicate debugging as the source code does not match the executed bytecode.

Implementation and Validation

Implementing a Record (JDK 16+)

Use a Record when you need a transparent, immutable data carrier and are targeting a modern JDK. Run this in any Java 16+ environment.

public record Order(Long id, String product, java.math.BigDecimal amount) {}

// Usage
Order order = new Order(1L, "Widget", new java.math.BigDecimal("99.99"));
System.out.println(order.product()); // Accessor is the field name, not getProduct()

Implementing Lombok @Value (JDK 8+)

Use @Value when you are constrained to an older JDK or need the class to extend a base class. Ensure the Lombok dependency is added to your pom.xml or build.gradle and annotation processing is enabled in your IDE.

import lombok.Value;

@Value
public class Order {
    Long id;
    String product;
    java.math.BigDecimal amount;
}

// Usage
Order order = new Order(1L, "Widget", new java.math.BigDecimal("99.99"));
System.out.println(order.getProduct()); // Standard JavaBean getter

Verifying the Result

To verify that a Record is truly immutable and correctly structured, run the javap command on the compiled .class file:

# Run in terminal after compilation
javap -v Order.class

Check the output for private final modifiers on all fields and the presence of the canonical constructor. For Lombok, verify the build logs to ensure the annotation processor executed successfully; if the IDE flags getProduct() as a missing method despite the annotation, the Lombok plugin is likely missing or disabled.

Limitations and Risks

• Framework Compatibility: Some older frameworks rely heavily on the getXXX and setXXX naming convention (JavaBeans). Records use name() instead of getName(), which may require updating your JSON mapping configuration (e.g., adding the jackson-module-parameter-names module).
• Build Tooling: Lombok requires specific configuration in Maven/Gradle to ensure the annotation processor runs before the compiler. Failure to do this will result in cannot find symbol errors during the build process.