RFR: 8273471: Add foldmultilines to UL for stdout/err [v2]

[Yasumasa Suenaga]

On Thu, 9 Sep 2021 05:58:43 GMT, Ioi Lam <iklam at openjdk.org> wrote:

> Also, if the user specifies foldmultilines multiple times for stdout/stderr
> 
> ```
> -Xlog:exceptions:::foldmultilines=true -Xlog:cds:::foldmultilines=false
> ```
> 
> Do we (or should) we print a warning message?
> 
> Today we'd get an warning with a command like the following, and the second foldmultilines=false is ignored. I think stdout/stderr should have the same behavior. (But the current message is too vague and should be improved, maybe in a different RFE).

I saw same issue in JDK 16, so I want to fix it as another RFE. I will file it later.


$ /usr/lib/jvm/java-16-openjdk/bin/java -Xlog:os=warning:file=test.log::filecount=1 -Xlog:exceptions=
info:file=test.log::filecount=1 --version
[0.000s][warning][logging] Output options for existing outputs are ignored.
openjdk 16.0.2 2021-07-20
OpenJDK Runtime Environment 21.3 (build 16.0.2+7)
OpenJDK 64-Bit Server VM 21.3 (build 16.0.2+7, mixed mode, sharing)


So can you review this change?

> test/hotspot/jtreg/runtime/logging/FoldMultilinesTest.java line 102:
> 
>> 100:         test("file=" + EXCEPTION_LOG_FILE);
>> 101:         test("stdout");
>> 102:         test("stderr");
> 
> I think we should add a case whe the output is not explicitly specified. I.e.,
> 
> 
> -Xlog:exceptions=info:::foldmultilines=true

I added test for this pattern in new commit.

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

PR: https://git.openjdk.java.net/jdk/pull/5407