I have a JSON model with A child property that has lots of fields which I would like to ignore. For example

{
    "id": 1,
    "preference": {
        "subproperty1": "dummy",
        "subproperty2": "dummy",
        "subproperty3": "dummy",
        ...
        "subproperty40": "dummy",
    },
    "property1": "dummy",
    "property2": "dummy",
    ...
    "property30": "dummy",
}

My expected deserialized result would be something look like

{
    "id": 1,
    "preference": {
        "subproperty1": "dummy",
        "subproperty2": "dummy",
    },
    "property1": "dummy",
    "property2": "dummy"
}

Meaning I would like to ignore lots of fields in my current and nested class, I know there is a @JsonIgnoreProperties to use such as

@JsonIgnoreProperties({"name", "property3", "property4", ..., "property30"})
@JsonSerialize(include = JsonSerialize.Inclusion.NON_EMPTY)
protected static class MixInMyClass {

}
...
objectMapper.getDeserializationConfig().addMixInAnnotations(MyClass.class, MixInMyClass.class);

• Question1: how could I ignore my nested fields (e.g, subproperty3, subproperty4... subproperty30) in "preference" on top of MixInMyClass?

• Question2: is there any easier way like a JsonRequired which plays as the opposite behavior and only allows certain needed fields in? So I don't need to have lots of unwanted fields as in jsonIgnore, but just few items like (id, property1, property2)

CodePudding user response：

1. To my knowledge no. You need to place the @JsonIgnoreProperties in nested classes as well.
2. Take a look at [JSON Views][1]. With it, you can tell which properties to include in each view. You could have 1 view:

public class Views {
    public static class Public {
    }
}

Then in your model you would need to annotate the properties you want to be avialble with @JsonView(Views.Public.class). Finally, in your endpoints, you would use @JsonView(Views.Public.class).

CodePudding user response：

You can simply fix this by annotating @JsonIgnoreProperties(ignoreUnknown = true).

Here is an example,

@JsonIgnoreProperties(ignoreUnknown = true)
class YouMainClass {
    private Integer id;
    private Preference preference;
    private String property1;
    private String property2;

    // getters & setters
}

@JsonIgnoreProperties(ignoreUnknown = true)
class Preference {
    private String property1;
    private String property2;

    // getters & setters
}

Use this YouMainClass to deserialize the JSON. All the unknow/unwanted properties will be ignored when deserializing.