Request Review: JDK-6479237 (cl) Add support for classloader names

[Brent Christian]

Hi, Mandy

It looks pretty good to me.  Just a couple small things:

* StackTraceElement.java

  379             ClassLoader loader = cls.getClassLoader0();

It looks as if 'loader' isn't used...?


* Throwable.java

  832             // VM to fill in StackTraceElement
  833             getStackTraceElements(stackTrace);
  834             // ensure the proper StackTraceElement initialization
  835             for (StackTraceElement ste : stackTrace) {
  836                 ste.buildLoaderModuleClassName();
  837             }

For my own curiosity, why is this buildLoaderModuleClassName() call needed?

Thanks,
-Brent

On 10/25/16 4:10 PM, Mandy Chung wrote:
> Webrev at:
>    http://cr.openjdk.java.net/~mchung/jdk9/webrevs/6479237/webrev.00/
>
> Specdiff:
>    http://cr.openjdk.java.net/~mchung/jdk9/webrevs/6479237/specdiff/overview-summary.html
>
> This is a long-standing RFE for adding support for class
> loader names.  It's #ClassLoaderNames on JSR 376 issue
> list where the proposal [1] has been implemented in jake
> for some time.  This patch brings this change to jdk9.
>
> A short summary:
> - New constructors are added in ClassLoader, SecureClassLoader
>   and URLClassLoader to specify the class loader name.
>
> - New ClassLoader::getName and StackTraceElement::getClassLoaderName
>   method
>
> - StackTraceElement::toString is updated to include the name
>   of the class loader and module of that frame in this format:
>      <loader>/<module>/<fully-qualified-name>(<src>:<line>)
>
> The detail is in StackTraceElement::buildLoaderModuleClassName
> that compress the output string for cases when the loader
> has no name or the module is unnamed module.  Another thing
> to mention is that VM sets the Class object when filling in
> a stack trace of a Throwable object.  Then the library will
> build a String from the Class object for serialization purpose.
>
> Mandy
> [1] http://mail.openjdk.java.net/pipermail/jpms-spec-observers/2016-September/000550.html
>