JAVA - Using same POJO but with less fields (without jackson)-CodePudding

I have a POJO used by an existing endpoint, this endpoint responds with all fields present in the POJO.
But I'm creating a new enpoint which should respond only some of the fields of the same POJO.
I want to avoid copying the same POJO file and deleting the parameters I don't need, is there a way to do this?

This is the POJO:

public class AgentChatStatus {

  private UUID activeChat;
  private List<AgentChat> chatRequests; //Object with less params on new endpoint
  private List<AgentChat> chatsOnHold; //Object with less params on new endpoint
  private Collection<Agent> agents;
  private int totalChatRequests;
  private int totalChatsOnHold;
  private Preferences.AgentConsoleConfig config;
// ...
}

public class AgentChat implements Payload {
  private UUID id;
  private String queueId;

Lets say I only need to show "Id" in endpoint 2 but id and queueId in endpoint1. I work with spring btw. Thanks!

CodePudding user response：

With Jackson you can take advantage of JSON Views. The first thing is to create the Views as follows:

public class Views {
    public static class ViewEndpoint2 { // The name can be whatever you want
    }

    public static class ViewEndpoint1 extends ViewEndpoint2 {
    }
}

Then you need to annotate the properties in your POJO with @JsonView so that you tell Jackson in which views such properties should be visible:

public class AgentChatStatus {

  @JsonView(Views.ViewEndpoint2.class)
  private UUID activeChat;

  @JsonView(Views.ViewEndpoint2.class)
  private List<AgentChat> chatRequests;

  @JsonView(Views.ViewEndpoint2.class)
  private List<AgentChat> chatsOnHold;

  @JsonView(Views.ViewEndpoint2.class)
  private Collection<Agent> agents;

  @JsonView(Views.ViewEndpoint2.class)
  private int totalChatRequests;

  @JsonView(Views.ViewEndpoint2.class)
  private int totalChatsOnHold;

  @JsonView(Views.ViewEndpoint2.class)
  private Preferences.AgentConsoleConfig config;

}

public class AgentChat implements Payload {
  @JsonView(Views.ViewEndpoint2.class)
  private UUID id;

  @JsonView(Views.ViewEndpoint1.class)
  private String queueId;
}

Finally, you need to annotate the endpoints with the corresponding view:

@JsonView(Views.ViewEndpoint1.class)
@RequestMapping("your-old-enpoint")
public void yourOldEndpoint() {
    (...)
}

@JsonView(Views.ViewEndpoint2.class)
@RequestMapping("your-new-enpoint")
public void yourNewEndpoint() {
    (...)
}

@JsonView(Views.ViewEndpoint1.class) basically means all properties in AgentChatStatus and AgentChat and @JsonView(Views.ViewEndpoint2.class) means only some of them (the ones annotated with @JsonView(Views.ViewEndpoint2.class)).

You can read more about this at https://www.baeldung.com/jackson-json-view-annotation.