Question about PolyNull on this

[Jon Schewe]

I'm working on upgrading to Checker Frameowrk 3.47.0 from 3.42.0.

I cam across the error below.

/home/jpschewe/projects/fll-sw/working-dir/src/main/java/fll/documents/writers/SubjectivePdfWriter.java:405: error: [methodref.receiver] Incompatible receiver type

.anyMatch(Goal::isRequired);

^

found : @Initialized @NonNull Goal

required: @Initialized @PolyNull Goal

Consequence: method in @Initialized @NonNull Goal

@Initialized @NonNull boolean isRequired(@Initialized @NonNull Goal this)

is not a valid method reference for method in @Initialized @NonNull Predicate<@Initialized @PolyNull Goal>

@Initialized @NonNull boolean test(@Initialized @NonNull Predicate<@Initialized @PolyNull Goal> this, @Initialized @PolyNull Goal p0)

The method signature on isRequire is below:

public boolean isRequired() {

Changing the method signature to this removes the error:

public boolean isRequired(@PolyNull Goal this) {

I read about PolyNull and I'm not sure how "this" being able to be null makes sense. Is this really the right way to correct this error? Is this a bug? Am I missing something else?

Jon