[GROOVY-7528] AssertionError at sun.reflect.generics.reflectiveObjects.WildcardTypeImpl.getLowerBoundASTs since Groovy 2.4.0 upgrade

• Type: Bug
• Status: Closed
• Priority: Minor
• Resolution: Cannot Reproduce
• Affects Version/s: 2.4.4
• Assignee: Paul King
• Reporter: Adrien Grand
• Created: 30/Jul/15 07:45
• Updated: 26/Aug/18 01:50
• Resolved: 26/Aug/18 01:50

Description

Since we upgraded from Grooy 2.4.0 to Groovy 2.4.4, we have been seeing occasional assertion errors in sun.reflect.generics.reflectiveObjects.WildcardTypeImpl.getLowerBoundASTs.

Here is the relevant stack trace:

java.lang.AssertionError
	at sun.reflect.generics.reflectiveObjects.WildcardTypeImpl.getLowerBoundASTs(WildcardTypeImpl.java:94)
	at sun.reflect.generics.reflectiveObjects.WildcardTypeImpl.getLowerBounds(WildcardTypeImpl.java:165)
	at com.sun.beans.TypeResolver.resolve(TypeResolver.java:176)
	at com.sun.beans.TypeResolver.resolve(TypeResolver.java:218)
	at com.sun.beans.TypeResolver.resolve(TypeResolver.java:169)
	at com.sun.beans.TypeResolver.resolveInClass(TypeResolver.java:81)
	at java.beans.FeatureDescriptor.getReturnType(FeatureDescriptor.java:370)
	at java.beans.Introspector.getTargetEventInfo(Introspector.java:996)
	at java.beans.Introspector.getBeanInfo(Introspector.java:417)
	at java.beans.Introspector.getBeanInfo(Introspector.java:163)
	at java.beans.Introspector.getBeanInfo(Introspector.java:250)
	at java.beans.Introspector.<init>(Introspector.java:397)
	at java.beans.Introspector.getBeanInfo(Introspector.java:163)
	at java.beans.Introspector.getBeanInfo(Introspector.java:250)
	at java.beans.Introspector.<init>(Introspector.java:397)
	at java.beans.Introspector.getBeanInfo(Introspector.java:163)
	at java.beans.Introspector.getBeanInfo(Introspector.java:250)
	at java.beans.Introspector.<init>(Introspector.java:397)
	at java.beans.Introspector.getBeanInfo(Introspector.java:163)
	at groovy.lang.MetaClassImpl$15.run(MetaClassImpl.java:3292)
	at java.security.AccessController.doPrivileged(Native Method)
	at groovy.lang.MetaClassImpl.addProperties(MetaClassImpl.java:3290)
	at groovy.lang.MetaClassImpl.initialize(MetaClassImpl.java:3266)
	at org.codehaus.groovy.reflection.ClassInfo.getMetaClassUnderLock(ClassInfo.java:254)
	at org.codehaus.groovy.reflection.ClassInfo.getMetaClass(ClassInfo.java:285)
	at org.codehaus.groovy.runtime.metaclass.MetaClassRegistryImpl.getMetaClass(MetaClassRegistryImpl.java:257)
	at org.codehaus.groovy.runtime.InvokerHelper.getMetaClass(InvokerHelper.java:875)
	at groovy.lang.GroovyObjectSupport.<init>(GroovyObjectSupport.java:34)
	at groovy.lang.Script.<init>(Script.java:42)
	at groovy.lang.Script.<init>(Script.java:39)
	at Script4.<init>(Script4.groovy)
	at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
	at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)
	at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
	at java.lang.reflect.Constructor.newInstance(Constructor.java:526)
	at java.lang.Class.newInstance(Class.java:374)
	at org.elasticsearch.script.groovy.GroovyScriptEngineService.createScript(GroovyScriptEngineService.java:129)
	at org.elasticsearch.script.groovy.GroovyScriptEngineService.access$100(GroovyScriptEngineService.java:57)
	at org.elasticsearch.script.groovy.GroovyScriptEngineService$1.getLeafSearchScript(GroovyScriptEngineService.java:165)
	at org.elasticsearch.search.aggregations.support.ValuesSource$Numeric$WithScript.doubleValues(ValuesSource.java:314)
	at org.elasticsearch.search.aggregations.metrics.sum.SumAggregator.getLeafCollector(SumAggregator.java:74)
	at org.elasticsearch.search.aggregations.AggregatorBase.getLeafCollector(AggregatorBase.java:132)
	at org.elasticsearch.search.aggregations.AggregatorBase.getLeafCollector(AggregatorBase.java:131)
	at org.elasticsearch.search.aggregations.AggregatorBase.getLeafCollector(AggregatorBase.java:38)
	at org.apache.lucene.search.MultiCollector.getLeafCollector(MultiCollector.java:117)
	at org.apache.lucene.search.IndexSearcher.search(IndexSearcher.java:762)
	at org.elasticsearch.search.internal.ContextIndexSearcher.search(ContextIndexSearcher.java:196)
	at org.apache.lucene.search.IndexSearcher.search(IndexSearcher.java:485)
	at org.elasticsearch.search.internal.ContextIndexSearcher.search(ContextIndexSearcher.java:174)
	at org.apache.lucene.search.IndexSearcher.search(IndexSearcher.java:694)
	at org.apache.lucene.search.IndexSearcher.searchAfter(IndexSearcher.java:410)
	at org.apache.lucene.search.IndexSearcher.search(IndexSearcher.java:439)
	at org.elasticsearch.search.query.QueryPhase.execute(QueryPhase.java:151)

I found this old thread suggesting that the JDK code may not be correct and asking whether someone saw this assertion trip in the wild: http://osdir.com/ml/core-libs-dev/2014-11/msg00337.html so this might be a JDK bug rather than a Groovy bug. However we didn't see this assertion error before we upgraded, so maybe there is a related Groovy change that made it more likely to happen? Like the email thread mentions, one reason why few people hit this assertion error might be that few people run with system assertions (-esa).

We have only seen this assertion trip on a JDK 7 (not 8) but I couldn't find any information related to fixing WildcardTypeImpl between JDK7 and JDK8, so I'm not totally sure the problem is fixed if running with JDK 8. It might just be rarer.

If you have confidence this is a JDK bug and not a Groovy bug, please feel free to close it. Hopefully this will at least serve for future reference if anyone else hits the same issue.