[OpenJDK 2D-Dev] RFR: 6986863: ProfileDeferralMgr throwing ConcurrentModificationException [v5]

[Alexander Zuev]

On Fri, 22 Jan 2021 10:35:13 GMT, Sergey Bylokhov <serb at openjdk.org> wrote:

>> This change intended to enhance the lazy initialization of the standard color profiles concurrently by different threads.
>> 
>> We defer standard profiles loading because most of UI application uses a small amount of data from the profile like numComponents and colorSpaceType, and this data is known in advance. But any other profile-related activity (like a color conversion, profile data accesses, etc.) triggers profile activation when we load all profile data to the memory.
>> 
>> Before the fix for JDK-6793818, we defer only one sRGB color profile, see: https://github.com/openjdk/jdk/commit/2726f2a3621dd2562d4fb660b4c3d376c65027aa
>> 
>> Notes about the link above:
>> - The code in the ProfileDeferralMgr, which contain the Vector of profiles for activation does not use any synchronization
>> - The `activateDeferredProfile` and `activate` methods are implemented to throw `ProfileDataException`, but this exception is ignored during activation process: 
>>     https://github.com/openjdk/jdk/commit/2726f2a3621dd2562d4fb660b4c3d376c65027aa#diff-0839c25a6c999452be28b431c54d5daa91364d302cfda6efa5c56421c2f2bdcbR96
>> 
>> The fix:
>>  - Drops the usage of ProfileDeferralMgr (which contained the Vector of profiles for activation) and ProfileActivator machinery. Instead, we will have just one `ICC_Profile.activate()` method which will activate and initialize the `ICC_Profile.cmmProfile` if it is null
>>  - The `activate` method implementation mimics the old behavior when the CMMException and IOException were wrapped by the ProfileDataException, and the ProfileDataException itself was ignored during activation - > so an exception will not be thrown in the method itself, but only when the null profile will be used.
>> 
>> See some comments inline.
>
> Sergey Bylokhov has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains 14 commits:
> 
>  - Merge branch 'master' into JDK-6986863
>  - Merge branch 'master' into JDK-6986863
>  - Update ProfileActivationDuringPropertyAccess.java
>  - Merge branch 'master' into JDK-6986863
>  - Merge branch 'master' into JDK-6986863
>  - Merge branch 'master' into JDK-6986863
>  - Merge branch 'master' into JDK-6986863
>  - Delete the DeferralMgr machinery
>  - Update ICC_Profile.java
>  - Wrong spec in ProfileDeferralInfo
>  - ... and 4 more: https://git.openjdk.java.net/jdk/compare/14522800...ecfc1ed8

test/jdk/java/awt/color/ICC_ProfileRGB/MTMatrixAccess.java line 54:

> 52:                 }
> 53:                 try {
> 54:                     rgb.getMatrix();

What should happen when this method is called on profile that is not activated yet? Should you just check that it returns the non-null array of correct size?

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PR: https://git.openjdk.java.net/jdk/pull/1613