Read embedded object in Jackson

Question

I\'m trying to read a legacy JSON code using Jackson 2.0-RC3, however I\'m stuck with an \"embedded\" object.

Given a following JSON:

{
    \"title\"         


        

Answer 1

I would deserialize the original JSON to a single, flat object first (kind of like an adapter), then create your own domain objects.

class ItemLegacy {
    private String title;

    @JsonProperty("date")
    private Date createdAt;

    @JsonPropery("author")
    private String name;

    @JsonPropery("author_avatar")
    private URL avatar;

    @JsonProperty("author_group")
    private Integer group;

    @JsonProperty("author_prop")
    private Integer group;
}

Then use this object to fill out your Item and Author objects and create the correct relationships.

 //... the deserialized original JSON
 ItemLegacy legacy ...

 // create an author
 Author author = new Author();
 author.setName(legacy.getName());
 author.setGroup(legacy.getGroup());
 ...

 // create an item
 Item item = new Item();
 item.setTitle(legacy.getTitle());
 ...

 // finally set the author... and you should have the desired structure
 item.setAuthor(author);

Your Item class could only be automatically deserialized from the following form:

{
    "title": "Hello world!",
    "date": "2012-02-02 12:23:34".
    "author": { 
                "name": "username", 
                "author_avatar": "http://...", 
                "author_group": "123", 
                "author_prop": "value" 
              }
}

You might be able to do something with custom deserialization, but it would not be the simpler solution for sure.