RFR: 8272805: Avoid looking up standard charsets [v2]

[Sergey Bylokhov]

On Sun, 22 Aug 2021 23:02:06 GMT, Sergey Bylokhov <serb at openjdk.org> wrote:

>> This is the continuation of JDK-8233884, JDK-8271456, and JDK-8272120.
>> 
>> In many places standard charsets are looked up via their names, for example:
>> absolutePath.getBytes("UTF-8");
>> 
>> This could be done more efficiently(up to x20 time faster) with use of java.nio.charset.StandardCharsets:
>> absolutePath.getBytes(StandardCharsets.UTF_8);
>> 
>> The later variant also makes the code cleaner, as it is known not to throw UnsupportedEncodingException in contrary to the former variant.
>> 
>> This change includes:
>>  * demo/utils
>>  * jdk.xx packages
>>  * Some places were missed in the previous changes. I have found it by tracing the calls to the Charset.forName() by executing tier1,2,3 and desktop tests.
>> 
>> Some performance discussion: https://github.com/openjdk/jdk/pull/5063
>> 
>> Code excluded in this fix: the Xerces library(should be fixed upstream), J2DBench(should be compatible to 1.4), some code in the network(the change there are not straightforward, will do it later).
>> 
>> Tested by the tier1/tier2/tier3 tests on Linux/Windows/macOS.
>
> Sergey Bylokhov has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains 14 additional commits since the last revision:
> 
>  - Update the usage of Files.readAllLines()
>  - Update datatransfer
>  - Merge branch 'master' into standard-encodings-in-non-public-modules
>  - Merge branch 'master' into standard-encodings-in-non-public-modules
>  - Fix related imports
>  - Merge branch 'master' into standard-encodings-in-non-public-modules
>  - Cleanup UnsupportedEncodingException
>  - Update PacketStream.java
>  - Rollback TextTests, should be compatible with jdk1.4
>  - Rollback TextRenderTests, should be compatible with jdk1.4
>  - ... and 4 more: https://git.openjdk.java.net/jdk/compare/be695a9b...e7127644

Can somebody take a look too the changes in the "jdk.attach", "jdk.hotspot.agent" and IdealGraphVisualizer?

-------------

PR: https://git.openjdk.java.net/jdk/pull/5210