@Override
      public void visitMethodReferenceExpression(@NotNull PsiMethodReferenceExpression methodRef) {
        if (!OptionalUtil.OPTIONAL_OF_NULLABLE.methodReferenceMatches(methodRef)) return;
        CommonDataflow.DataflowResult dfr = CommonDataflow.getDataflowResult(methodRef);
        if (dfr == null) return;
        PsiElement anchor = methodRef.getReferenceNameElement();
        if (anchor == null) return;
        DfType type = dfr.getDfType(new JavaMethodReferenceArgumentAnchor(methodRef));
        processArgument(type, anchor);
      }
@Override
      public void visitMethodReferenceExpression(@NotNull PsiMethodReferenceExpression methodRef)