[OpenJDK 2D-Dev] [11] RFR: [JDK-4954348]: JPGWriter.getNumThumbnailsSupported does not return -1 when passing null values

[Jayathirth D V]

Hi Phil,

> Test case works properly before and after the code change.
? You mean it does not fail before the fix ?
It definitely fails for me before the fix.

- I mean as intended Phil. It fails before the fix and after the fix it passes.

> Since we are touching getNumThumbnailsSupported() function and it is only overridden in JPEGImageWriter we can add override annotation for the same.

I would be more inclined to address that in a separate bug that adds the annotation for all the over-ridden JPEG reader+writer methods, rather than adding just one in the file.

- Sure. We can take that in separate bug.

Thanks,
Jay

-----Original Message-----
From: Philip Race 
Sent: Tuesday, March 27, 2018 2:39 AM
To: Jayathirth D V
Cc: Prahalad Kumar Narayanan; 2d-dev
Subject: Re: [OpenJDK 2D-Dev] [11] RFR: [JDK-4954348]: JPGWriter.getNumThumbnailsSupported does not return -1 when passing null values



On 3/23/18, 2:21 AM, Jayathirth D V wrote:
> Hi Prahalad,
>
> Change looks fine.
> Test case works properly before and after the code change.
? You mean it does not fail before the fix ?
It definitely fails for me before the fix.
>
> Since we are touching getNumThumbnailsSupported() function and it is only overridden in JPEGImageWriter we can add override annotation for the same.

I would be more inclined to address that in a separate bug that adds the annotation for all the over-ridden JPEG reader+writer methods, rather than adding just one in the file.

-phil.
> Thanks,
> Jay
>
> -----Original Message-----
> From: Prahalad Kumar Narayanan
> Sent: Friday, March 23, 2018 1:40 PM
> To: 2d-dev
> Subject: [OpenJDK 2D-Dev] [11] RFR: [JDK-4954348]: 
> JPGWriter.getNumThumbnailsSupported does not return -1 when passing 
> null values
>
> Hello Everyone
>
> Good day to you.
>
> Request your time to review a simple fix for the bug
>      Bug: JDK-4954348 (https://bugs.openjdk.java.net/browse/JDK-4954348)
>      Title: JPGWriter.getNumThumbnailsSupported does not return -1 
> when passing null values
>
> Root Cause:
>      . As per ImageWriter specification, the method- getNumThumbnailsSupported, should return -1 when invoked with insufficient data.
>      . However, the method's implementation in JpegImageWriter returns 0 instead of -1 in this use-case.
>
> Information on the fix:
>      . The logic within concerned method of Jpeg image writer requires one of the two inputs- ImageTypeSpecifer (or) IIOMetadata.
>      . If both the required inputs are 'Null' the method has insufficient data&  thus cannot validate.
>      . A simple check is now added in the method to detect this use-case and return -1 as recommended in the specification.
>
> Kindly review the changes at your convenience
> Link: http://cr.openjdk.java.net/~pnarayanan/4954348/webrev.00
>
> Thank you
> Have a good day
>
> Prahalad N.