Why is Lombok @Builder not compatible with this constructor?

Question

I have this simple code:

@Data @Builder public class RegistrationInfo {      private String mail;     private String password;      public RegistrationInfo(RegistrationInfo registrationInfo) {         this.mail = registrationInfo.mail;         this.password = registrationInfo.password;     } } 

First I was using only the @Builder Lombok annotation and everything was fine. But I added the constructor and the code does not compile any more. The error is:

Error:(2, 1) java: constructor RegistrationInfo in class com.user.RegistrationInfo cannot be applied to given types;   required: com.user.RegistrationInfo   found: java.lang.String,java.lang.String   reason: actual and formal argument lists differ in length   

So I have two questions:

1. Why is Lombok @Builder not compatible with this constructor?
2. How do I make the code compile taking into account that I need both the builder and the constructor?

Answer 1

You can either add an @AllArgsConstructor annotation, because

@Builder generates an all-args constructor iff there are no other constructors defined.

(Quotting @Andrew Tobilko)

Or set an attribute to @Builder : @Builder(toBuilder = true) This give you the functionality of a copy constructor.

@Builder(toBuilder = true) class Foo {     // fields, etc }  Foo foo = getReferenceToFooInstance(); Foo copy = foo.toBuilder().build();