自定义串行器和 Jackson 架构

Question

I have the following two classes:

public class MyChild
{
    @JsonProperty
    public int x;
}
public class MyTest
{
    public void MyChild() {}

    @JsonSerialize(using = MapValueSerializer.class)
    private Map<String, MyChild> childs = new LinkedHashMap<>();
}

where I want childs to serialize as an array of MyChild and not as a map (values only). Thus, I use the following custom serializer:

public class MapValueSerializer extends StdSerializer<Map<String, ?>>
{

    protected MapValueSerializer()
    {
        this(null);
    }

    protected MapValueSerializer(Class<Map<String, ?>> t)
    {
        super(t);
    }

    @Override
    public void serialize(Map<String, ?> value, JsonGenerator gen, SerializerProvider provider) throws IOException
    {
        provider.defaultSerializeValue(value.values(), gen);
    }
}

When I now use the JsonSchemaGenerator to generate a schema from MyTest , I get the following:

{
  "type" : "object",
  "id" : "urn:jsonschema:com:myclasses:MyTest",
  "properties" : {
    "childs" : {
      "type" : "any"
    }
  }
}

But childs shouldn't be of type "any" but of type "object". If I remove the serializer, the type is "object". Do I have to add something to make the schema generator aware of that type?

Answer 1

It works after I overwrite acceptJsonFormatVisitor() in my MapValueSerializer class with:

@Override
public void acceptJsonFormatVisitor(JsonFormatVisitorWrapper visitor, JavaType typeHint) throws JsonMappingException
{
    JavaType valueType = ((MapType) typeHint).getContentType();
    visitor.getProvider().findValueSerializer(valueType).acceptJsonFormatVisitor(visitor, valueType);
}

Then child is of type "object" and also the subelement "x" is generated in the schema.