@Nullable static HighlightInfo checkModuleReference(@Nullable PsiJavaModuleReferenceElement refElement) { if (refElement != null) { PsiPolyVariantReference ref = refElement.getReference(); assert ref != null : refElement.getParent(); if (ref.multiResolve(false).length == 0) { String message = JavaErrorMessages.message("module.ref.unknown", refElement.getReferenceText()); return HighlightInfo.newHighlightInfo(HighlightInfoType.WRONG_REF) .range(refElement) .description(message) .create(); } } return null; }