[GROOVY-3406] GroovyRuntimeException thrown Ambiguous method overloading when accessing metaClas of java.lang.String

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.6-rc-1, 1.6
• Fix Version/s: 1.6.4, 1.7-beta-1
• Component/s: groovy-jdk
• Environment: Ubuntu Linux, jdk 1.6, Eclipse 3.4.1
• Assignee: Jochen Theodorou
• Reporter: James Parkin
• Created: 13/Mar/09 04:52
• Updated: 18/May/09 10:20
• Resolved: 18/May/09 10:20

Description

Running the following code cause an Ambiguous method overloading exception:

str = 'hello'
methodName = 'toUpperCase'

methodOfInterest = str.metaClass.getMetaMethod(methodName)
println methodOfInterest.invoke(str)

Expected output: HELLO

Exception details:

Exception in thread "main" groovy.lang.GroovyRuntimeException: Ambiguous method overloading for method org.codehaus.groovy.runtime.HandleMetaClass#getMetaMethod.
Cannot resolve which method to invoke for

{class java.lang.String}

due to overlapping prototypes between:

{class java.lang.String, class [Ljava.lang.Object;} {class java.lang.String, class [Ljava.lang.Class;}

at groovy.lang.MetaClassImpl.chooseMostSpecificParams(MetaClassImpl.java:2866)
at groovy.lang.MetaClassImpl.chooseMethod(MetaClassImpl.java:2819)
at groovy.lang.MetaClassImpl.getNormalMethodWithCaching(MetaClassImpl.java:1228)
at groovy.lang.MetaClassImpl.getMethodWithCaching(MetaClassImpl.java:1131)
at groovy.lang.MetaClassImpl.invokeMethod(MetaClassImpl.java:910)
at groovy.lang.MetaClassImpl.invokeMethod(MetaClassImpl.java:892)
at org.codehaus.groovy.runtime.InvokerHelper.invokePogoMethod(InvokerHelper.java:736)
at org.codehaus.groovy.runtime.InvokerHelper.invokeMethod(InvokerHelper.java:719)
at org.codehaus.groovy.runtime.ScriptBytecodeAdapter.invokeMethodN(ScriptBytecodeAdapter.java:163)
at MOPUsingMetaMethod.run(MOPUsingMetaMethod.groovy:4)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.codehaus.groovy.reflection.CachedMethod.invoke(CachedMethod.java:86)
at groovy.lang.MetaMethod.doMethodInvoke(MetaMethod.java:234)
at groovy.lang.MetaClassImpl.invokeMethod(MetaClassImpl.java:1061)
at groovy.lang.MetaClassImpl.invokeMethod(MetaClassImpl.java:892)
at org.codehaus.groovy.runtime.InvokerHelper.invokePogoMethod(InvokerHelper.java:736)
at org.codehaus.groovy.runtime.InvokerHelper.invokeMethod(InvokerHelper.java:719)
at org.codehaus.groovy.runtime.InvokerHelper.runScript(InvokerHelper.java:381)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.codehaus.groovy.reflection.CachedMethod.invoke(CachedMethod.java:86)
at groovy.lang.MetaMethod.doMethodInvoke(MetaMethod.java:234)
at groovy.lang.MetaClassImpl.invokeStaticMethod(MetaClassImpl.java:1301)
at org.codehaus.groovy.runtime.InvokerHelper.invokeMethod(InvokerHelper.java:710)
at org.codehaus.groovy.runtime.ScriptBytecodeAdapter.invokeMethodN(ScriptBytecodeAdapter.java:163)
at MOPUsingMetaMethod.main(MOPUsingMetaMethod.groovy)

This functionality does work in groovy 1.5.7 so appears to have regressed in 1.6.0.

Using the pickMethod instead of getMetaMethod produces the expected output.