> Jackson should not create any list. To be more specific, You do not want to create any list and ur looking for a such feature.
What we can do here is write a custom deserializer to do such thing and there is already plenty references on the web 2024년 10월 18일 (금) 오전 4:04, [email protected] <[email protected]>님이 작성: > My class contains an initialized custom collection > > class MyClass { > > MyList<Integer> myList = MyList.create(); > } > > where MyList is a j.u.List. When deserializing, I get an exception saying > that there is no known deserializer for MyList ("Cannot find a deserializer > for non-concrete List type"), which is generally understandable, but I > already initialized it, so there's no need for one. Instead, I just want to > add the items to the list. > To demonstrate, I can add a private setter inside the class: > > private void setMyList(List<Integer> ints) { ints.forEach(MyList::add); } > > this works, but I don't think it should be needed. Specifically, Jackson > should not create any list. It needs to deserialize the values of the items > anyway; then instead of creating a list, add them to the existing one. It's > a List, so it should know to call 'add' ('put' for map). > > I know there is @JsonMerge, and I thought that that's what I needed, but > just adding it to the field doesn't work, I still get the same exception. > Am I not understanding @JsonMerge or am I doing something wrong? > > Thanks! > > -- > You received this message because you are subscribed to the Google Groups > "jackson-user" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To view this discussion on the web visit > https://groups.google.com/d/msgid/jackson-user/af74c8b0-1516-4cc8-9117-be6808cf9223n%40googlegroups.com > <https://groups.google.com/d/msgid/jackson-user/af74c8b0-1516-4cc8-9117-be6808cf9223n%40googlegroups.com?utm_medium=email&utm_source=footer> > . > -- You received this message because you are subscribed to the Google Groups "jackson-user" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/jackson-user/CALS-ipxQQhVLYiRZf%2B5bjFq%3DnGs2ePnDH6VL1C9gBWC4jrescg%40mail.gmail.com.
