Java 14 records canonical constructor

[Remi Forax]

----- Mail original -----
> De: "Christian Beikov" <christian.beikov at gmail.com>
> À: "Johannes Kuhn" <info at j-kuhn.de>
> Cc: "amber-dev" <amber-dev at openjdk.java.net>
> Envoyé: Jeudi 4 Juin 2020 20:43:39
> Objet: Re: Java 14 records canonical constructor

> Am 04.06.2020 um 20:24 schrieb Johannes Kuhn:
>> They need to be mutable to do defensive copies, thereby enforcing deep
>> immutability. Consider this:
>>
>> public record UserRecord(String userName, List<String> mailAddresses) {
>>     public UserRecord {
>>         mailAddresses = List.copyOf(mailAddresses);
>>     }
>> }
>>
>> Records would be a lot less useful if this is not possible.
> 
> This could be done through a static factory method as well.
> 
> public record UserRecord(String userName, List<String> mailAddresses) {
>     public static UserRecord create(String userName, List<String>
> mailAddresses) {
>         return new UserRecord(userName, List.copyOf(mailAddresses));
>     }
> }
> 

Nope, because serialization is based on the canonical constructor.

Rémi