[infinispan-issues] [JBoss JIRA] (ISPN-9072) Document Protobuf annotated collection null set callbacks

Document Protobuf annotated collection null set callbacks --------------------------------------------------------- Key: ISPN-9072 URL: https://issues.jboss.org/browse/ISPN-9072 Project: Infinispan Issue Type: Task Components: Documentation-Query Affects Versions: 9.2.1.Final Reporter: Galder Zamarreño Assignee: Adrian Nistor Fix For: 9.4.0.Final When using collection fields in Protobuf annotated classes, empty collections are marshalled into the same value as {{null}}, because Protobuf only has repeated fields and no fields is represented as {{null}}. This means that if you have an entity with an empty collection, when it's deserialized the collection will be null. This can be confusing for users and should be documented. [~anistor] had some ideas on how to improve this: {code} <anistor> I'm thinking of a way to make this easier for users that would prefer an empty collection being set instead of a null. would be possible by adding a new attribute for this in @ProtoField anotation > that'd be more predictable <anistor> would still not give you at deserializtion what was written during serialization. we do not have a null marker <anistor> it would just give you an empty collection if you prefer <anistor> instead of null > that option should be enabled by default {code}