Groovy does not run on IBM JRE6

Do you get the same error with even a trivial Groovy hello world example or only with Grails?

The same happens when I try to run the groovy console for example:

t343r:/opt/groovy-1.5.0/bin# ./groovyConsole
java.lang.reflect.InvocationTargetException
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:45)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:612)
at org.codehaus.groovy.tools.GroovyStarter.rootLoader(GroovyStarter.java:101)
at org.codehaus.groovy.tools.GroovyStarter.main(GroovyStarter.java:130)
Caused by: java.lang.ExceptionInInitializerError
at java.lang.J9VMInternals.initialize(J9VMInternals.java:220)
at org.codehaus.groovy.runtime.Invoker.<init>(Invoker.java:38)
at org.codehaus.groovy.runtime.InvokerHelper.<clinit>(InvokerHelper.java:44)
at java.lang.J9VMInternals.initializeImpl(Native Method)
at java.lang.J9VMInternals.initialize(J9VMInternals.java:198)
at org.codehaus.groovy.runtime.ScriptBytecodeAdapter.getProperty(ScriptBytecodeAdapter.java:472)
at groovy.ui.Console.main(Console.groovy:117)
... 6 more
Caused by: java.lang.ClassCastException: java.lang.reflect.Method incompatible with java.lang.Comparable
at java.util.Arrays.binarySearch(Unknown Source)
at java.util.Arrays.binarySearch(Unknown Source)
at org.codehaus.groovy.reflection.CachedMethod.find(CachedMethod.java:59)
at groovy.lang.MetaClassImpl.applyPropertyDescriptors(MetaClassImpl.java:1759)
at groovy.lang.MetaClassImpl.setupProperties(MetaClassImpl.java:1529)
at groovy.lang.MetaClassImpl.addProperties(MetaClassImpl.java:2418)
at groovy.lang.MetaClassImpl.initialize(MetaClassImpl.java:2398)
at org.codehaus.groovy.runtime.metaclass.MetaClassRegistryImpl.<init>(MetaClassRegistryImpl.java:99)
at org.codehaus.groovy.runtime.metaclass.MetaClassRegistryImpl.<init>(MetaClassRegistryImpl.java:63)
at groovy.lang.GroovySystem.<clinit>(GroovySystem.java:27)
at java.lang.J9VMInternals.initializeImpl(Native Method)
at java.lang.J9VMInternals.initialize(J9VMInternals.java:198)
... 12 more

This appears to hinge on the following throws clause in Arrays.binarySearch(Object[] array, Object key)...

ClassCastException - if the search key in not comparable to the elements of the array.

Does this require for all i :

array[i].compareTo(key)

or for all i :

key.compareTo(array[i])

? It looks like Sun is calling the former, and IBM the latter. Since the key is a Method, it doesn't implement Comparable (whereas CachedMethod does). I think it may mean both, as the comparison must be commutative. Hence the IBM JDK is not in error in throwing the exception in my opinion.

My patch may cause a performance hit, but that may be eliminated by some cut and paste.

I may apply this tonight if I get time. First I need to boot into linux and verify it fixes the IBM JDK problem. IBM's JRE is not broadly availble for Windows.

My patch did the trick. Alex, since it's your optimization feel free to re-do if you don't like my solution.