Issues with Custom Serialization of Nested Objects in Java 17 Using Jackson
I'm trying to implement I'm stuck on something that should probably be simple..... I'm facing a problem with the custom serialization of nested objects using Jackson in my Java 17 application. I have a class `User` that contains a list of `Address` objects, and I'm trying to serialize this to JSON. However, the nested `Address` objects are not being serialized correctly, and I am getting an empty array for addresses in the output JSON. Here's my code for the `User` class: ```java import com.fasterxml.jackson.annotation.JsonProperty; import java.util.List; public class User { private String name; @JsonProperty("addresses") private List<Address> addressList; public User(String name, List<Address> addressList) { this.name = name; this.addressList = addressList; } // Getters public String getName() { return name; } public List<Address> getAddressList() { return addressList; } } ``` And my `Address` class looks like this: ```java import com.fasterxml.jackson.annotation.JsonProperty; public class Address { @JsonProperty("street") private String street; @JsonProperty("city") private String city; public Address(String street, String city) { this.street = street; this.city = city; } } ``` When I serialize an instance of `User` like this: ```java import com.fasterxml.jackson.databind.ObjectMapper; public class Main { public static void main(String[] args) throws Exception { List<Address> addresses = List.of(new Address("123 Main St", "Springfield")); User user = new User("John Doe", addresses); ObjectMapper objectMapper = new ObjectMapper(); String jsonResult = objectMapper.writeValueAsString(user); System.out.println(jsonResult); } } ``` I get the following output: ``` {"name":"John Doe","addresses":[]} ``` I've confirmed that the `addressList` is not empty before serialization, and I suspect it might be a problem with how the Jackson annotations are set up or how the `ObjectMapper` is configured. I've tried adding `@JsonInclude(JsonInclude.Include.NON_EMPTY)` to both classes, but that didn't change the result. What am I missing here to get the nested objects serialized correctly? Any suggestions would be helpful. Is this even possible?