Jackson Inheritance - spring-boot

Question

Can't seem to figure this out. I keep getting various errors so I'll just write this with the current error I'm getting from Jackson.
public class ResponseDetail {
private Response response;
}
#JsonTypeInfo(use = JsonTypeInfo.Id.NAME)
#JsonSubTypes({
#JsonSubTypes.Type(value = ResponseTypeOne.class, name = "ResponseTypeOne"),
#JsonSubTypes.Type(value = ResponseTypeTwo.class, name = "ResponseTypeTwo"),
#JsonSubTypes.Type(value = ResponseTypeThree.class, name = "ResponseTypeThree")
})
#JsonIgnoreProperties(ignoreUnknown = true)
public abstract class Response {
}
In other packages I have these three:
public class ResponseTypeOne extends Response {
private Integer status;
}
public class ResponseTypeTwo extends Response {
private String message;
}
public class ResponseTypeThree extends Response {
private String value;
}
Error:
Caused by: com.fasterxml.jackson.databind.exc.InvalidTypeIdException: Missing type id when trying to resolve subtype of [simple type, class com.services.models.Response]: missing type id property '#type' (for POJO property 'response')
I have tried various iterations of this #JsonTypeInfo with various includes and various property's also with Id.CLASS with no luck.

Answer 1

You need to declare how the type should be recognized.
#JsonTypeInfo(use = JsonTypeInfo.Id.NAME, include = JsonTypeInfo.As.EXISTING_PROPERTY, property = "#ttype")
#JsonSubTypes({
#JsonSubTypes.Type(value = ResponseTypeOne.class, name = "ResponseTypeOne"),
#JsonSubTypes.Type(value = ResponseTypeTwo.class, name = "ResponseTypeTwo"),
#JsonSubTypes.Type(value = ResponseTypeThree.class, name = "ResponseTypeThree")
})
#JsonIgnoreProperties(ignoreUnknown = true)
public abstract class Response {
#JsonProperty("#ttype")
public abstract String getChildType();
}
And in child types do like below:
#JsonTypeName("ResponseTypeOne")
public class ResponseTypeOne extends Response {
#Override
public String getChildType() {
return "ResponseTypeOne";
}
}
And incoming json should be like below to enable jackson to find the correct child implementation:
{
//some attributes of child Response
"#ttype": "ResponseTypeOne"
}