[GROOVY-660] Multi-threaded groovy: get java.lang.LinkageError: duplicate class definition

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.0-beta-8
• Fix Version/s: 1.0-beta-9
• Environment: eclipse 3.1M1, Sun JDK1.5.0
• Assignee: Sam Pullara
• Reporter: Andre R. Pareis
• Created: 02/Nov/04 18:22
• Updated: 24/Mar/06 06:23
• Resolved: 02/Jan/05 18:33

Description

I just switched to groovy, which is great BTW.

I have an example which I can't get to work when I execute it in parallel in two threads within the same VM.

It's about this type of code:

Binding context = new Binding();
GroovyShell shell = new GroovyShell();
Script script = shell.parse("println 'foo'");
script.setBinding(context);
Object result = script.run();

I always get an exception during the multi-threaded execution:
java.lang.LinkageError: duplicate class definition: gjdk/groovy/lang/GroovyObjectSupport_GroovyReflector
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(ClassLoader.java:620)
at groovy.lang.GroovyClassLoader.defineClass(GroovyClassLoader.java:478)
at groovy.lang.MetaClassRegistry$2.run(MetaClassRegistry.java:153)
at java.security.AccessController.doPrivileged(Native Method)
at groovy.lang.MetaClassRegistry.loadClass(MetaClassRegistry.java:151)
at groovy.lang.MetaClass.loadReflectorClass(MetaClass.java:2250)
at groovy.lang.MetaClass.loadReflector(MetaClass.java:2232)
at groovy.lang.MetaClass.generateReflector(MetaClass.java:2182)
at groovy.lang.MetaClass.checkInitialised(MetaClass.java:2129)
at groovy.lang.MetaClassRegistry.getMetaClass(MetaClassRegistry.java:121)
at groovy.lang.MetaClass.addNewStaticMethodsFrom(MetaClass.java:1281)
at groovy.lang.MetaClass.addInheritedMethods(MetaClass.java:212)
at groovy.lang.MetaClass.checkInitialised(MetaClass.java:2126)
at groovy.lang.MetaClassRegistry.getMetaClass(MetaClassRegistry.java:121)
at org.codehaus.groovy.runtime.Invoker.getMetaClass(Invoker.java:99)
at org.codehaus.groovy.runtime.InvokerHelper.getMetaClass(InvokerHelper.java:94)
at groovy.lang.GroovyObjectSupport.<init>(GroovyObjectSupport.java:61)
at groovy.lang.Binding.<init>(Binding.java:62)

When I run this code single-threaded, it works fine. Seems like a 'sometimes-per-thread, sometimes-global' thing to me.

Thanks
Andre