Jackson cannot convert empty string value to enum

Question

I am looking for a handy solution with Jackson (2.8) to filter out fields pointing to empty String value before/during deserialization:

@JsonInclude(JsonInclude.Include.NON_EMPTY)
public class Guis {

public enum Context {
    SDS,
    NAVIGATION
}

public enum Layer {
    Library,
    Status,
    Drivingdata
}

// client code

 String s = "{\"context\":\"\",\"layer\":\"Drivingdata\"}";
 ObjectMapper mapper = new ObjectMapper();
 Guis o = mapper.readValue(s, Guis.class);

Error

 Exception in thread "main" com.fasterxml.jackson.databind.exc.InvalidFormatException: Can not deserialize value of type cq.speech.rsi.api.Guis$Context from String "": value not one of declared Enum instance names: [SDS NAVIGATION] at [Source: {"context":"","layer":"Drivingdata"}; line: 1, column: 12] (through reference chain: cq.speech.rsi.api.Guis["context"])

What else I tried... Ah this one

mapper.getDeserializationConfig().with(DeserializationFeature.ACCEPT_EMPTY_STRING_AS_NULL_OBJECT);

The error remains and apparently even googling around didn't help much...

EDIT

set DeserializationFeature does not work as exemplified above. For me the solution was eventually to add this snippet:

 mapper.configure(DeserializationFeature.READ_UNKNOWN_ENUM_VALUES_AS_NULL, true)

Answer 1

You can enable DeserializationFeature.READ_UNKNOWN_ENUM_VALUES_AS_NULL for your mapper, its disabled by default. Only caveat to using this, it will treat all unknown including empty string as null for enum.