Can not deserialize instance of java.util.ArrayList out of VALUE_STRING

Question

I have a REST service built with Jersey and deployed in the AppEngine. The REST service implements the verb PUT that consumes an application/json media type. Th

Answer 1

from Jackson 2.7.x+ there is a way to annotate the member variable itself:

 @JsonFormat(with = JsonFormat.Feature.ACCEPT_SINGLE_VALUE_AS_ARRAY)
 private List newsletters;

More info here: Jackson @JsonFormat