用杰克逊反序列化嵌套的json对象

Question

I would like to ask you guys how to deserialize nested object with jackson. I got example Json File:

{
    "id": "1",              
    "comment": "Some comment",
    "user": "Smith",
    "date": "2018-05-31",
    "shape": "oval",
    "coordinates": [ ["50", "130"], ["370", "500"] ]
}, 

Let's say that main Class is called Comment , but I would like to create another class Coordinates with local variables x1, x2, y1, y2 . So class Comment looks like that:

 public class CommentFile implements Serializable{
    private Long id;
    private String comment;
    private String user;
    private String date;
    private String shape;
    private Coordinates coordinates;
    //setters, getters, constructor

But because in json i have 'array' "coordinates": [ ["50", "130"], ["370", "500"] ] , i dont know how to convert this to:

public class Coordinates implements Serializable{
private double x1;
private double y1;
private double x2;
private double y2;

Any ideas?

Answer 1

A straightforward way is to use List<List<String>> coordinates; to deserialize the JSON to Java first. Later, you can implement a method something like getCoordinatesObject() inside CommentFile class to create and get a Coordinates object.

There might be a better way to accomplish this directly with Jackson but you can do this as well.