RFR: 8297191: [macos] printing page range "page 2 to 2" or "page 2 to 4" on macOS leads to not print [v2]

[Alexey Ivanov]

On Mon, 25 Aug 2025 19:38:15 GMT, Alexey Ivanov <aivanov at openjdk.org> wrote:

>>> However, the fix resets the known range of pages to the full range of the document. Is it because the native code doesn't care about the range and it's handled in Java side?
>> 
>> It looks like the operating system does not expect the page range selected by the user here, but the number of pages in the document, even though it is queried as page range.
>> 
>> 
>>> Wouldn't it be easier then to always return NO from knowsPageRange? The fTotalPages field can be dropped from the PrinterView class.
>> 
>> Here we can only guess what exactly the operating system is doing in this case. For example, if the number of pages is not known, e.g. in streaming mode, the operating system must start with the first page and iterate through the pages until it reaches the desired page.
>> So I would let the operating system know the number of pages. It may help it to choose a more appropriate printing strategy.
>> 
>> 
>>> But why didn't the old code work? If a range is set to 2-3, we know exactly the number of pages to print, and this number is 2.
>> 
>> To answer this question, we need to look at the code of the operating system. But it seems that the operating system needs the total number of pages here, not the range selected by the user.
>> The documentation page does not describe it in detail either.
>> 
>>> Does it work correctly if mDocument.getNumberOfPages() in CPrinterJob.java returns a certain number instead of UNKNOWN_NUMBER_OF_PAGES?
>> 
>> I tried both variants and it does not work.
>
>> > Does it work correctly if mDocument.getNumberOfPages() in CPrinterJob.java returns a certain number instead of UNKNOWN_NUMBER_OF_PAGES?
>> 
>> I tried both variants and it does not work.
> 
> You didn't answer the question, so I had to write a test which also uses `Pageable` and returns the number of pages.
> 
> No, it doesn't work as expected *without* your suggested fix.
> 
> Yes, it does behave as expected *with* the fix. We're good.

> Wouldn't it be easier then to always return `NO` from `knowsPageRange`? The `fTotalPages` field can be dropped from the `PrinterView` class.

Returning `NO` doesn't work at all. I had to test it myself. I get an error message dialog displayed: *Error while printing.*

Yet I still think the `fTotalPages` field can be dropped from the `PrinterView` class. It serves no real purpose and its value is often incorrect. For example, if the total number of pages returned by `Pageable` is 10, the value of `fTotalPages` is set to 10 too, even if the range 10-10 is requested.

I tested that setting `aRange->length` to `NSIntegerMax` always works. Therefore, the code can be simplified by getting rid of `fTotalPages`.

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PR Review Comment: https://git.openjdk.org/jdk/pull/11266#discussion_r2298973332