public static Nullability inferNullability(@NotNull PsiParameter parameter) {
    if (parameter.getType() instanceof PsiPrimitiveType) return Nullability.UNKNOWN;
    PsiParameterList parent = ObjectUtils.tryCast(parameter.getParent(), PsiParameterList.class);
    if (parent == null) return Nullability.UNKNOWN;
    PsiMethodImpl method = ObjectUtils.tryCast(parent.getParent(), PsiMethodImpl.class);
    if (method == null) return Nullability.UNKNOWN;

    BitSet notNullParameters = getInferenceData(method).notNullParameters;
    if (!notNullParameters.isEmpty()) {
      int index = parent.getParameterIndex(parameter);
      if (notNullParameters.get(index)) {
        return Nullability.NOT_NULL;
      }
    }
    return Nullability.UNKNOWN;
  }
public static Nullability inferNullability(@NotNull PsiParameter parameter)