Hi David,
any news on https://bugs.openjdk.java.net/browse/JDK-8212117?
I do not see any activity on this :(
Thanks,
Egor
On 09-Apr-19 15:53, David Holmes wrote:
On 9/04/2019 7:36 pm, Egor Ushakov wrote:
Hi David,
you're right! The fix for JDK-8212117 should help here as well.
After that fix we may want to revisit ValueContainer.findType
implementors, currently they all (except for ArrayTypeImpl)
delegates to ReferenceTypeImpl.findType (which ends up in
classloader.visibleClasses).
ArrayTypeImpl inherits findType from ReferenceTypeImpl.
The issue is only the non-public findComponentType method.
Someone should clarify the difference between
classLoader.visibleClasses and allClasses filtered by the classLoader
instance then.
That would be good, I just don't know if there is anyone who would
know (as opposed to trying to figure it out).
In my opinion fixing JDK-8212117 is risky and requires heavy testing,
do you think it may be fixed any time soon?
Yes it's under way but the person doing it is away this week.
Thanks,
David
Thanks,
Egor
On 09-Apr-19 08:15, David Holmes wrote:
Hi Egor,
I want to re-emphasise that once JDK-8212117 is fixed then this bug
should also be fixed.
On 5/04/2019 8:30 pm, Egor Ushakov wrote:
Hi David, thanks for your comments!
I'm not sure how findComponentType worked in the current state:
Type findComponentType(String signature) throws
ClassNotLoadedException {
93 byte tag = (byte)signature.charAt(0);
94 if (PacketStream.isObjectTag(tag)) {
95 // It's a reference type
96 JNITypeParser parser = new JNITypeParser(componentSignature());
97 List<ReferenceType> list = vm.classesByName(parser.typeName());
98 Iterator<ReferenceType> iter = list.iterator();
99 while (iter.hasNext()) {
100 ReferenceType type = iter.next();
101 ClassLoaderReference cl = type.classLoader();
102 if ((cl == null)?
103 (classLoader() == null) :
104 (cl.equals(classLoader()))) {
105 return type;
106 }
107 }
108 // Component class has not yet been loaded
109 throw new ClassNotLoadedException(componentTypeName());
110 } else {
111 // It's a primitive type
112 return vm.primitiveTypeMirror(tag);
113 }
114 }
the method receives signature string but uses it only for object
checking, then inside it does the search by componentSignature()
instead...
Most probably the method is always called passing
componentSignature() string as a parameter anyway.
Regarding the fix:
the only thing I'm trying to change here is where the requested
type name is looked at - loader.visibleClasses (this is where
findType ends up) instead of vm.classesByName.
This is how it works in all other implementors of
com.sun.tools.jdi.ValueContainer.findType.
Yes but I'm trying to determine why the difference exists - if we
already had loader.findType then why go to the bother of writing
findComponentType that way instead of just using findType? My
concern is that (ignoring the bug with not-initialized classes) the
set of classes returned by loader.visibleClasses may be different to
that which can be found via vm.classesByName.
I'm not convinced we have adequate test coverage in this area.
ArrayTypeImpl.type() is unused, so I'm not sure how it was supposed
to be used and where.
Tracking the relationships between classes/interfaces here is quite
tricky and it had appeared to me that ArrayTypeImpl.type() could end
up getting used. But I've re-scanned the code and that seems not to
be the case. For good measure I changed it to always throw an
exception and re-ran all the JDI tests (though as I said coverage
seems limited) with no problems.
If this is truly unused then we should delete it to avoid future
confusion - a separate RFE would be fine for that.
Thanks,
David
I've run all jdi tests and see no regression, probably
ClassNotLoadedException is never thrown in this case.
Removed the test from the ProblemList in the new cr:
http://cr.openjdk.java.net/~eushakov/8221503/webrev.01/
On 05-Apr-19 07:58, David Holmes wrote:
Hi Egor,
This doesn't seem right to me sorry ...
On 2/04/2019 7:42 pm, Egor Ushakov wrote:
Please review the fix
this test started to fail after the fix of
https://bugs.openjdk.java.net/browse/JDK-8146986
previously any call to ClassLoaderReference.visibleClasses as a
side effect cached the results in
VirtualMachineImpl.typesBySignature
and made them available to any VirtualMachine.classesByName call.
This is somewhat not consistent for unprepared classes, I
reported that, check
Bug 26148990 : JDI - VirtualMachine.allClasses does not return
loaded but uninitialized class,
That issue is now a duplicate of this core-libs issue:
https://bugs.openjdk.java.net/browse/JDK-8212117
which is in the process of being fixed. Once it is fixed then this
workaround would no longer be needed.
That said I'm not at all clear how the proposed workaround
actually works-around the underlying issue.
but it seems that it allowed the ArrayTypeImpl.componentType to
work even if the type was not prepared,
check how ArrayTypeImpl#findComponentType uses vm.classesByName.
It seems that ArrayTypeImpl#findComponentType should simply call
findType for component signature.
Just how the unused com.sun.tools.jdi.ArrayTypeImpl#type method
works, not sure why it was dropped...
The package-private:
Type type() throws ClassNotLoadedException {
return findType(elementSignature());
}
seems to have always existed but never been used as the
implementation for the public componentType() method (previously
elementType()). In fact the two methods appear to have different
requirements with regards to what they should be returning. AFAICS:
- ArrayTypeImpl.type() returns the actual array type
- ArrayTypeImpl.componentType() returns the actual ultimate
component type
i.e if I understand correctly, given double[][][] then
- ArrayTypeImpl.type() == double[][]
- ArrayTypeImpl.componentType() == double
so implementing them both the same way can't possibly be correct!
bugid https://bugs.openjdk.java.net/browse/JDK-8221503
cr http://cr.openjdk.java.net/~eushakov/8221503/webrev.00/
Thanks!
<http://cr.openjdk.java.net/~eushakov/8221503/webrev.00/>
You'd also need to update the ProblemList so the test gets
re-enabled.
diff -r 532e88de77eb test/hotspot/jtreg/ProblemList.txt
--- a/test/hotspot/jtreg/ProblemList.txt
+++ b/test/hotspot/jtreg/ProblemList.txt
@@ -161,8 +161,6 @@
vmTestbase/nsk/jdi/VirtualMachine/redefineClasses/redefineclasses021/TestDescription.java
8065773 generic-all
vmTestbase/nsk/jdi/VirtualMachine/redefineClasses/redefineclasses023/TestDescription.java
8065773 generic-all
-vmTestbase/nsk/jdb/eval/eval001/eval001.java 8221503 generic-all
-
vmTestbase/metaspace/gc/firstGC_10m/TestDescription.java 8208250
generic-all
vmTestbase/metaspace/gc/firstGC_50m/TestDescription.java 8208250
generic-all
vmTestbase/metaspace/gc/firstGC_99m/TestDescription.java 8208250
generic-all
It also appears to me that the exception message of the
ClassNotLoadedException will be different now. Have you re-run all
the JDI tests?
Thanks,
David
-----
--
Egor Ushakov
Software Developer
JetBrains
http://www.jetbrains.com
The Drive to Develop
--
Egor Ushakov
Software Developer
JetBrains
http://www.jetbrains.com
The Drive to Develop
--
Egor Ushakov
Software Developer
JetBrains
http://www.jetbrains.com
The Drive to Develop
