jackson serialization of nested objects

问题

I have problem with jackson serialization of object by its interface.

I have class

class Point implements PointView {

    private String id;

    private String name;

    public Point() {

    }

    public Point(String id, String name) {
        this.id = id;
        this.name = name;
    }

    @Override
    public String getId() {
        return id;
    }

    public String getName() {
        return name;
    }

}

which implements

interface PointView {
    String getId();
}

and have class

class Map implements MapView {

    private String id;

    private String name;

    private Point point;

    public Map() {

    }

    public Map(String id, String name, Point point) {
        this.id = id;
        this.name = name;
        this.point = point;
    }

    @Override
    public String getId() {
        return id;
    }

    public String getName() {
        return name;
    }

    @JsonSerialize(as = PointView.class)
    public Point getPoint() {
        return point;
    }

}

which implements

interface MapView {
    String getId();
    Point getPoint();
}

And have class

class Container {

    private Map map;

    public Container() {

    }

    public Container(Map map) {
        this.map = map;
    }

    @JsonSerialize(as = MapView.class)
    public Map getMap() {
        return map;
    }
}

I want serialize Container with Jackson and get result

{"map":{"id":"mapId","point":{"id":"pointId"}}}

But in fact I get result

{"map":{"id":"mapId","point":{"id":"pointId","name":"pointName"}}}

that have property "name" in nested object "point" although I specified serializition type of Point in Map (@JsonSerialize(as = PointView.class)). Interface PointView dont have method getName, but in result exists field "name" of Point.

If I remove annotation (@JsonSerialize(as = MapView.class)) from method getMap in class Container I get result

{"map":{"id":"mapId","name":"mapName","point":{"id":"pointId"}}}

Now point dont have property "name", but map have.

How can I get result

{"map":{"id":"mapId","point":{"id":"pointId"}}}

回答1:

To get the desired result also the same method in interface must be annotated by @JsonSerialize

interface MapView {
    String getId();
    @JsonSerialize(as = PointView.class)
    Point getPoint();
}

回答2:

You can annotate the method like this:

@JsonIgnore
public String getName() {
    return name;
}

Or if you want specific serialization in this use case, but normal serialization in others, you can use a @JsonView (see doc).

The reason it's serializing out the name is that the instance has the accessor getName(), even though interface does not.

回答3:

Yes, you can use

@JsonSerialize(as=MyInterface.class)
public class ConcreteClass implements MyInterface { .... }

either on implementation class (as above), or on property that has value.

来源：https://stackoverflow.com/questions/33151974/jackson-serialization-of-nested-objects

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