running Groovy on JDK9

[Jochen Theodorou]

Hi all,

today I had a few hours spare time and decided to invest that in trying 
to make the Groovy build compile and run tests. I am not trying to make 
a module on my own yet.

for compilation to work my biggest problem was the direct usage of the 
javac compiler set through gradle. Which is why I had to add

options.forkOptions.jvmArgs << > options.forkOptions.jvmArgs << 
"-XaddExports:jdk.compiler/com.sun.tools.javac.api=ALL-UNNAMED"

for compileJava and
> groovyOptions.forkOptions.jvmArgs << "-XaddExports:jdk.compiler/com.sun.tools.javac.api=ALL-UNNAMED"

for the groovy compiler (which uses internally he compiler set through 
gradle)

those simple changes (and removing the deprecated jvm options) get me 
past compilation and into test execution, which completes with 47 
failures (of 8566 tests). First error I get is something like this:

>  Compile error during compilation with javac.
> /tmp/stubgentests77510877964035184621460309483098/bar/GroovyClass.java:12: error: package groovy.lang does not exist
> groovy.lang.GroovyObject {

as an explanation.. at this point there should be a groovy.jar 
containing GroovyObject on the classpath. There is a GroovyClass.groovy, 
for which a GroovyClass.java stub is produced. The stub is then used 
during the compilation of java sources, that depend on groovy sources 
and the other way around. The stub does have only dummy code. But I am 
wondering why this compilation fails. We do use the sources option 
during compilation with javac and javac finds them.. only it seems those 
sources have no access to the groovy.jar

Then of course we have something like this:
> org.codehaus.groovy.runtime.m12n.ExtensionModuleTest > testThatModuleCanBeLoadedWithGrab FAILED
>     java.lang.RuntimeException: Unable to find class loader

(module here has nothing to do with jigsaw. This error is caused by not 
using an URLClassloader anymore in JDK9... I actually would like to know 
what the jdk9 way of doing this is supposed to be. What I mean is that 
you had the not really supported option of adding a jar to the highest 
loader and make its classes available to lower loaders that way. Since 
that loader is no URLClassloader anymore, this does not work any longer. 
But is there any way to simulate that? Main usage was for example 
loading a sql driver jar via Class.forName and the driver then 
registering itself in the static constructor. How am I supposed to 
dynamically load database drivers in JDK9 (even if they are not written 
for JDK9)? Would be one question. But this extends to jars loaded at 
runtime, not through command line options containing services in general 
actually.

And then I have this one:
>
> org.codehaus.groovy.runtime.InterfaceConversionTest > testDefaultInterfaceMethodCallOnProxy FAILED
> BUG! UNCAUGHT EXCEPTION: access to public member failed: java.util.Comparator.reversed()Comparator/invokeSpecial, from java.util.Comparator/2 (module java.base)
> at org.codehaus.groovy.vmplugin.v7.Java7.getInvokeSpecialHandle(Java7.java:99)
> at org.codehaus.groovy.runtime.ConversionHandler.invoke(ConversionHandler.java:109)
> at com.sun.proxy.$Proxy47.reversed(Unknown Source)
> at java_util_Comparator$reversed$0.call(Unknown Source)
> at org.codehaus.groovy.runtime.callsite.CallSiteArray.defaultCall(CallSiteArray.java:48)
> at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:113)
> at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:117)
> at org.codehaus.groovy.runtime.InterfaceConversionTest.testDefaultInterfaceMethodCallOnProxy(InterfaceConversionTest.groovy:52)
>
> Caused by:
> java.lang.IllegalAccessException: access to public member failed: java.util.Comparator.reversed()Comparator/invokeSpecial, from java.util.Comparator/2 (module java.base)
> at java.lang.invoke.MemberName.makeAccessException(java.base at 9-ea/MemberName.java:870)
> at java.lang.invoke.MethodHandles$Lookup.checkAccess(java.base at 9-ea/MethodHandles.java:1642)
> at java.lang.invoke.MethodHandles$Lookup.checkMethod(java.base at 9-ea/MethodHandles.java:1582)
> at java.lang.invoke.MethodHandles$Lookup.getDirectMethodCommon(java.base at 9-ea/MethodHandles.java:1731)
> at java.lang.invoke.MethodHandles$Lookup.getDirectMethodNoSecurityManager(java.base at 9-ea/MethodHandles.java:1725)
> at java.lang.invoke.MethodHandles$Lookup.unreflectSpecial(java.base at 9-ea/MethodHandles.java:1336)
> at org.codehaus.groovy.vmplugin.v7.Java7.getInvokeSpecialHandle(Java7.java:96)
> ... 7 more

Can somebody explain me what the IllegalAccessException means? Why can I 
not call unreflectSpecial here?


bye Jochen