RFR(M): 8199852: Print more information about class loaders in LinkageErrors.

[David Holmes]

Hi Goetz,

Can you provide a detailed comparison of all the before and after 
messages please. It seems to me you are rewriting some of the messages 
in a way that changes the meaning.

src/hotspot/share/classfile/systemDictionary.cpp

Before:

!         linkage_error1 = "loader constraint violation: loader 
(instance of ";
!         linkage_error2 = ") previously initiated loading for a 
different type with name \"";

after:

!         linkage_error1 = "loader constraint violation: loader ";
!         linkage_error2 = " wants to load class ";
!         linkage_error3 = ". A different class with the same name was 
previously loaded by ";

this does not describe the same situation!

Thanks,
David

On 21/03/2018 9:55 PM, Lindenmaier, Goetz wrote:
> Hi,
> 
> ClassLoaders have a field containing a name since Java 9.
> 
> This change improves some of the messages of LinkageErrors to
> print the name of the loader involved, as well as the parent of the loader.
> This simplifies tracking down the component causing an error in large
> Java systems.
> 
> Please review:
> http://cr.openjdk.java.net/~goetz/wr18/8199852-exMsg_Linkage/01/index.html
> 
> I ran this through all our tests (jck, jtreg, spec etc).  I will run it through submit-hs
> (or jdk/submit) once it's reviewed.
> 
> Best regards,
>    Goetz.
> 
> 
> 
>