Use Lombok @RequiredArgsConstructor without @NonNull

问题

I have something like this:

@RequiredArgsConstructor
public class Person {
    private String name;
    private LocalDate date = null;
}

I need a constructor for the name attribute only, but it is not working. If I use @NonNull it will build the constructor I need, but for my case the name should be able to be null, can not be final either. Any ideas? Thanks!

回答1:

Lombok @RequiredArgsConstructor has no such option currently.

You have at least two options:

1. Just code the constructor public Person(String name) without help of lombok annotations.

2. Use inheritance - which might be a bit overkill solution in your case but might be handy in some cases - as presented below:

   • Create a base class that holds all the fields you do not want to be in Person constructor:

     public abstract class BasePerson {
         private LocalDate date = null;
     }
     

   • Let your Person class extend above with the fields you need in constructor but want to be null also, with @AllArgsConstructor:

     @AllArgsConstructor
     public abstract class Person extends BasePerson {
         private String name;
     }
     

来源：https://stackoverflow.com/questions/48790494/use-lombok-requiredargsconstructor-without-nonnull