I have been taking advantage of Jackson JSON parser to map out my objects. While testing out the api, I have come across an issue with creating/updating my object that includes nested objects.
Creating and Updating main object
Airplane plane = airplanes.get(planeId);
if(plane == null){
plane = mapper.readValue(jsonNode, Airplane.class)
}else{
mapper.readerForUpdating(plane).readValue(jsonNode);
}
Example of objects:
public class Airplane {
private static final String TAG = "Airplane Model";
@JsonProperty("id")
private String mId;
@JsonProperty("company")
private String mCompany;
@JsonProperty("pilot")
private Pilot mPilot;
@JsonProperty("passenger")
private Passenger mPassenger;
public Airplane() {
}
}
public class Pilot {
private static final String TAG = "Pilot Model";
@JsonProperty("id")
private String mId;
@JsonProperty("name")
private String mName;
public Pilot() {
//keeps getting called on airplane reader update
}
}
Everything maps correctly, however the issue is that every time an airplane object is updated, it creates a new nested object of 'Pilot' as commented in the Pilot() constructor. This becomes a larger issue because the airplane model is being updated by a web socket at a small time interval (Unnecessary object instantiation). Additionally, I am setting non-mapped fields in the Pilot object which are being lost due to a new Pilot object being created on every update.
What is the proper way to update an object via Jackson with nested objects? Am I missing any annotations to prevent repetitive instantiation of my nested objects.
