Jackson不能创建在ObjectMapper中已注册的类的实例

I have a parent object and a child object. The parent object may include the same child objects multiple times, so I only serialize the child object once and the next instances are only referenced by their ID. The object deserializes without errors when I remove the @JsonIdentityInfo annotation from the child object. To me this feels like a Jackson bug, but maybe someone spots an error in my code. I made a small example which shows the error (Jackson version used is 2.9.4): The parent class:I have a parent object and a child object. The