Does lombok @Builder allow extends

Question

I have 2 classes:

import lombok.Builder;
@Builder
public class B extends A {
}

and

import lombok.Builder;
@Builder
public class A {
}

on the @Builder on B I get the message:

The return type is incompatible with A.builder().

Is this a limitation of lombok? or something I'm doing wrong?

If I leave the @Builder off A, then the Builder on B doesn't seem to consider the fields in A in the constructors for B.

Answer 1

The latest lombok release 1.18.2 includes the new experimental @SuperBuilder. It supports inheritance and fields from superclasses (also abstract ones). The only requirement is that all superclasses must have the @SuperBuilder annotation. With it, the solution is as simple as this:

@SuperBuilder
public class B extends A {
   private String b;
}

@SuperBuilder
public class A {
    private String a;
}

B instance = B.builder().b("b").a("a").build();