反序列化序列化的非对称[JsonInclude]行为

Question

I have a class with a field, whose type is List<String> . I want to ignore empty list when serializaton so the field does not show in my json. But when deserializaton, I want it empty list will be included in my java object. @JsonInclude(Include.NON_EMPTY) will ignore it for both cases. should I write a custom serializDifferenter? What is the best approach for that?

Answer 1

Why you don't just initialize the List<String> to an empty ArrayList<String> in the Java object, just this way:

public class JsonTestObject implements Serializable {

    private String propertyOne = null;

    private Integer intProperty = 0;

    @JsonInclude(Include.NON_EMPTY)
    private List<String> stringList = new ArrayList<String>();
}

The serialization with an empty List will produce this kind of json:

{"propertyOne":"aaaaa","intProperty":1000}

And with a sinple deserialization ot this json sample, the List<String> will be initialized to an empty list