Private static field in Java interface
You cann't have a private static field in Java interface even though you use Java8 which you can have default implementation.
There is a hack for this.
public interface InterfaceContainsPrivateStaticFields { class _PrivateStaticFields { private static ObjectMapper mapper = new ObjectMapper(); // only accessible in this interface. } default ObjectReader test() { return _PrivateStaticFields.mapper.reader(); } }
You can see techniques that enable jackson processing faster in this PR.