RFR (S) 8023697: failed class resolution reports different class name in detail message for the ,first and subsequent times

Coleen Phillimore coleen.phillimore at oracle.com
Wed Apr 30 21:41:25 UTC 2014

Karen,  Thank you for looking at the code.

On 4/28/14, 6:11 PM, Karen Kinnear wrote:
> Coleen,
> A couple of comments/questions:
> 1. Can you possibly measure footprint in a large application to see if the saved error messages use significant footprint?

I ran medrec and dacapo.  Only failed constant pool resolutions are 
cached in this resolution error table.  For these applications there was 
only one entry in this hashtable, so the footprint increase for both the 
pointer and the refcounted Symbol (which is the class name) is 
mimimal.   The spec requires that the JVM throw the same exception for 
subsequent resolutions from the constant pool.  For the field and method 
cases, we repeat the resolution steps and get the same answer.   Only 
for classes, method handles and method types, do we save the resolution 
error.  The resolution error is for errors during class loading from 
constant pool symbolic reference in the spec 5.3 paragraph 1 and does 
not include errors for linking and initializing the class.  The error 
conditions for this are saved with a different mechanism 

> 2. I'm concerned about setting expectations that the detailed message will be repeated precisely for constant pool resolution
>      - but for now that is only for Class, MethodHandle and MethodType resolution

Since the JVM repeats the attempted resolution for these other types of 
constant pool resolution, the message will already be the same.

> 3. A comment in the bug report says that for linkage errors in SD the detail message is the name of the class, in all cases but this one, the
> message is the same
>     - I'm confused - did you test this with for instance a LoaderConstraint test - doesn't that have a different detail message?

I fixed the comment in the bug.  For the case in the test, where the 
error came from the super class not found, the message refers to the 
super class.  For all the other testing I did, since we save the name of 
the class in the error message.  The loader constraint test does not 
save the error in the resolution error table.

In investigating this, I found there were two  parameters unused in 
handle_resolution_exception() so cleaned them up too.

open webrev at http://cr.openjdk.java.net/~coleenp/8023697_2/

> I appreciate consolidating the duplicate code.
> thanks,
> Karen
> On Apr 28, 2014, at 5:07 PM, Coleen Phillimore wrote:
>> Summary: Cache detail message when we cache exception for constant pool resolution.
>> In the resolution error table.  Provide a default message if one is not in the original exception.  Also, consolidate duplicate code for MethodHandleInError and MethodTypeInError with UnresolvedClassInError.
>> open webrev athttp://cr.openjdk.java.net/~coleenp/8023697/
>> bug linkhttps://bugs.openjdk.java.net/browse/JDK-8023697
>> Ran jck8, ute vm.quick.testlist, jtreg tests in hotspot/test, java/lang/invoke jdk jtreg tests.
>> Thanks,
>> Coleen

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