RFR(S): 8131129: Attempt to define a duplicate BMH$Species class

[Peter Levart]

On 11/05/2015 02:16 PM, Michael Haupt wrote:
> Hi Claes, Peter, Vladimir, all,
>
> I really support Peter's latest proposal: it reduces the amounts of code, synchronisation, and complication, and actually addresses the problem at hand too. What's more to wish for? :-)
>
> I propose to adopt this solution: http://cr.openjdk.java.net/~plevart/jdk9-dev/BMH.race/webrev.03/
>
> Not sure how to proceed. Peter's name should be on the changeset. As he's a Committer, I'm fine if he pushes it once it's signed off by a Reviewer.
>
> Thanks,
>
> Michael

Hi Michael, Vladimir, Claes, all,

When I try the following example:

public class Test {

     static class Failure {
         static final int value;
         static {
             if (true) {
                 throw new InternalError("Failure");
             }
             value = 123;
         }
     }

     public static void main(String[] args) {
         try {
             Field valueField = Failure.class.getDeclaredField("value");
             int value = valueField.getInt(null);
             System.out.println("Got value: " + value);
         } catch (Throwable e) {
             System.out.println("\n1st exception:\n");
             e.printStackTrace(System.out);
         }

         try {
             Field valueField = Failure.class.getDeclaredField("value");
             int value = valueField.getInt(null);
             System.out.println("Got value: " + value);
         } catch (Throwable e) {
             System.out.println("\n2nd exception:\n");
             e.printStackTrace(System.out);
         }
     }
}


...I get the following output:


1st exception:

java.lang.InternalError: Failure
     at Test$Failure.<clinit>(Test.java:12)
     at sun.misc.Unsafe.ensureClassInitialized(Native Method)
     at 
sun.reflect.UnsafeFieldAccessorFactory.newFieldAccessor(UnsafeFieldAccessorFactory.java:43)
     at 
sun.reflect.ReflectionFactory.newFieldAccessor(ReflectionFactory.java:142)
     at java.lang.reflect.Field.acquireFieldAccessor(Field.java:1088)
     at java.lang.reflect.Field.getFieldAccessor(Field.java:1069)
     at java.lang.reflect.Field.getInt(Field.java:574)
     at Test.main(Test.java:21)

2nd exception:

java.lang.NoClassDefFoundError: Could not initialize class Test$Failure
     at sun.misc.Unsafe.ensureClassInitialized(Native Method)
     at 
sun.reflect.UnsafeFieldAccessorFactory.newFieldAccessor(UnsafeFieldAccessorFactory.java:43)
     at 
sun.reflect.ReflectionFactory.newFieldAccessor(ReflectionFactory.java:142)
     at java.lang.reflect.Field.acquireFieldAccessor(Field.java:1088)
     at java.lang.reflect.Field.getFieldAccessor(Field.java:1069)
     at java.lang.reflect.Field.getInt(Field.java:574)
     at Test.main(Test.java:30)


The 1st attempt that also tries to initialize the class throws 
InternalError directly from <clinit>, but the 2nd attempt is a kind of 
LinkageError, which is a different type. So in order for the test(s) to 
pass, we have to consider this secondary exception too as a non-critical 
exception:

http://cr.openjdk.java.net/~plevart/jdk9-dev/BMH.race/webrev.04/

I think this is better then trying to disguise NoClassDefFoundError into 
a VirtualMachineError just in order to "fool" the test(s). This is how 
VM operates and in general, Error(s) thrown by VM should be propagated 
up to the top and reported as-is.

Regards, Peter

>
>> Am 05.11.2015 um 12:07 schrieb Claes Redestad <claes.redestad at oracle.com>:
>>
>>
>> On 2015-11-05 08:00, Peter Levart wrote:
>>>
>>> Ok, here it is:
>>>
>>> http://cr.openjdk.java.net/~plevart/jdk9-dev/BMH.race/webrev.03/
>>>
>>> I just moved CACHE registration into SpeciesData.initForBootstrap() method, so no new method is needed. Note that patched source now contains the same number of lines as original. How does the jigsaw HelloWorld score now?
>>>
>>> Regards, Peter
>> Thanks, this looks really good to me. I verified that #classes are the same and it even looks like footprint improves ever so slightly.
>>
>> /Claes