Lombok: How to define a special method which runs upon the Object construction?

Question

I have a @Value @AllArgsConstructor class, and I want each instance of it to have an ID(The first object has the ID of 1, the second is 2, etc..). until now, before I used lombok but a constructor, my solution used to be: private static int idsCounter = 0; and then this.id = ++idsCounter; inside the constructor.

so how am I supposed to implement this with Lombok which eliminates the constuctor?

what if I have many fields? It'll be annoying to write the constructor myself(and use @Getter).. Are you sure that there's no feature to add some code(like a method) which would be applied to created Object? — Techno Freak, Sep 10 '19 at 22:33
as per https://stackoverflow.com/questions/41156010/is-there-any-postconstruct-feature-of-lombok and https://github.com/rzwitserloot/lombok/issues/1207, it's not a thing — iluxa, Sep 10 '19 at 22:51
Annoying? How long do you think it will take? More than 15 minutes? — VGR, Sep 11 '19 at 02:21
You can bypass the constructor and write something like : `private int id = IDCounter.incrementAndGet();` — bubbles, Sep 15 '19 at 11:15

score 0 · Answer 1 · answered Jun 26 '23 at 23:33

Add an initialisation block:

@AllArgsConstructor
class MyClass {
    static int idsCounter = 0;
    private int id;
    // other fields
    
    {
        id = ++idsCounter;
    }
}

This block runs after the constructor.

It's not a perfect solution because you'll have to provide a value for id, but just provide 0 as it will be overridden by the code in the block.

Lombok: How to define a special method which runs upon the Object construction?

1 Answers1