Lombok @Builder继承如何同时支持父类与子类构建？

Absolutely, Lombok can handle scenarios where both a parent class and its child need their own functional @Builder implementations—you just need to use the right approach to avoid the method conflict you're encountering.

Recommended Approach: Use @SuperBuilder (Lombok 1.18.4+) #

Lombok introduced the @SuperBuilder annotation specifically to solve inheritance-related Builder issues. It automatically handles parent class properties in the child's Builder, and lets both classes have their own independent Builder APIs.

Step-by-Step Implementation #

1. Add @SuperBuilder to your parent class:

@SuperBuilder
public class Parent {
    private final String parentProperty;
}

2. Add @SuperBuilder to your child class (which extends the parent):

@SuperBuilder
public class Child extends Parent {
    private final String childProperty;
}

Usage Examples #

• Build an instance of the parent class:

Parent parent = Parent.builder()
    .parentProperty("Parent value")
    .build();

• Build an instance of the child class (with access to both parent and child properties):

Child child = Child.builder()
    .parentProperty("Parent value")
    .childProperty("Child value")
    .build();

This approach is clean, maintainable, and avoids all manual workaround code.

Legacy Workaround (For Lombok Versions <1.18.4) #

If you're stuck on an older Lombok version that doesn't support @SuperBuilder, you can resolve the method name conflict by renaming the child class's Builder method, and explicitly include parent properties in the child's Builder.

Implementation #

1. Add @Builder to the parent class as usual:

@Builder
@AllArgsConstructor
public class Parent {
    protected String parentProperty;
}

2. For the child class, use builderMethodName to rename its Builder method (to avoid conflicting with the parent's builder()), and add @AllArgsConstructor to ensure the child's constructor includes parent properties:

@Builder(builderMethodName = "childBuilder")
@AllArgsConstructor
public class Child extends Parent {
    private String childProperty;
}

Usage Examples #

• Build a parent instance:

Parent parent = Parent.builder()
    .parentProperty("Parent value")
    .build();

• Build a child instance using the renamed Builder method:

Child child = Child.childBuilder()
    .parentProperty("Parent value")
    .childProperty("Child value")
    .build();

While this works, it's less elegant than @SuperBuilder and requires more manual setup.

内容的提问来源于stack exchange，提问作者IgorGudkov