Jackson 不序列化字段

Question

I have the following class -

public class Entity {

    private String id;
    private String name;

    private List<Image> images = new ArrayList<>();

    public String getId() {
        return id;
    }

    public void setId(String id) {
        this.id = id;
    }

    public void add(Image image) {
        this.images.add(image);
    }
}

public class Image {

    private String width;
    private String height;
    private String url;

    public String getWidth() {
        return width;
    }

    public void setWidth(String width) {
        this.width = width;
    }

    public String getHeight() {
        return height;
    }

    public void setHeight(String height) {
        this.height = height;
    }

    public String getUrl() {
        return url;
    }

    public void setUrl(String url) {
        this.url = url;
    }
}

I am using the objectMapper.valueToTree(sections) to convert it to a JsonNode. However when I print the same I see only the id and name field from the Entity class and not anything from the Images list. Do I need to add any kind of special logic or annotation to make sure the List gets printed out as well.

The following is the main class -

    public static void main(String[] args) {

        Entity entity = new Entity();

        entity.setId("1");

        Image image = new Image();

        image.setWidth("300");
        image.setHeight("100");
        image.setUrl("www.ca.com");

        entity.add(image);

        ObjectMapper objectMapper = new ObjectMapper();
        System.out.println(objectMapper.valueToTree(entity));
    }

Answer 1

You need to add getter and setter for Entity#images