I figured it out:

The GroovyShell belongs to the parent classloader and thus ginq cannot find it 
when the classloader lacks a parent. One solution is to use the parentless 
classloader to create the GroovyShell e.g:

var c = cl.loadClass("groovy.lang.GroovyShell");
var shell = c.getDeclaredConstructor().newInstance();
c.getMethod("evaluate", String.class).invoke(shell, script);

Another way is to use a ProcessBuilder but that is much more involved for my 
current use case.

Regards,
Per

From: Per Nyfelt <p...@alipsa.se>
Organisation: Alipsa HB
Reply to: "users@groovy.apache.org" <users@groovy.apache.org>
Date: Monday, 28 April 2025 at 20:23
To: "users@groovy.apache.org" <users@groovy.apache.org>
Subject: Running ginq from a "clean" classloader


Hi,

I am experimenting with running groovy scripts in a "clean" environment i.e. in 
a GroovyClassloader that does not have a parent.

Background: One of my OSS projects is an analytics IDE where i want to enable 
users to run scripts that only has the dependencies of a gradle build script 
and hence i need to separate the IDE classloader from the one running the 
script.

However, i have run into an issue with ginq expressions that baffles me.

A complete but minimal example is here: 
https://github.com/perNyfelt/groovy-issues/tree/main/NoParentCL but the issue 
is basically:

The groovy script is

def numbers = [0, 1, 2]

println "Numbers are $numbers"

var result = GQ {

    from n in numbers

    where n > 0

    select n

}

println "Ginq result is $result"

After creating the GroovyClassloader i add the following files to the 
classpath:  groovy-4.0.26.jar, groovy-ginq-4.0.26.jar, groovy-macro-4.0.26.jar

When is do

new GroovyShell(new GroovyClassloader()).evaluate(script)

everything works fine but if i do

new GroovyShell(new GroovyClassloader((Classloader)null).evaluate(script)

I get

Exception in thread "main" groovy.lang.MissingMethodException: No signature of 
method: Script1.GQ() is applicable for argument types: (Script1$_run_closure1) 
values: [Script1$_run_closure1@5cb5bb88]
Possible solutions: is(java.lang.Object), run(), run(), any(), grep(), 
any(groovy.lang.Closure)
        at 
org.codehaus.groovy.runtime.ScriptBytecodeAdapter.unwrap(ScriptBytecodeAdapter.java:72)
        at 
org.codehaus.groovy.vmplugin.v8.IndyGuardsFiltersAndSignatures.unwrap(IndyGuardsFiltersAndSignatures.java:163)
        at 
org.codehaus.groovy.vmplugin.v8.IndyInterface.fromCache(IndyInterface.java:321)
        at Script1.run(Script1.groovy:3)
        at 
java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:103)
        at java.base/java.lang.reflect.Method.invoke(Method.java:580)
        at 
org.codehaus.groovy.reflection.CachedMethod.invoke(CachedMethod.java:343)
        at groovy.lang.MetaMethod.doMethodInvoke(MetaMethod.java:328)
        at groovy.lang.MetaClassImpl.doInvokeMethod(MetaClassImpl.java:1333)
        at groovy.lang.MetaClassImpl.invokeMethod(MetaClassImpl.java:1088)
        at groovy.lang.MetaClassImpl.invokeMethod(MetaClassImpl.java:1007)
        at 
org.codehaus.groovy.runtime.InvokerHelper.invokePojoMethod(InvokerHelper.java:633)
        at 
org.codehaus.groovy.runtime.InvokerHelper.invokeMethod(InvokerHelper.java:624)
        at 
org.codehaus.groovy.runtime.InvokerHelper$1.run(InvokerHelper.java:461)
        at groovy.lang.GroovyShell.evaluate(GroovyShell.java:460)
        at groovy.lang.GroovyShell.evaluate(GroovyShell.java:495)
        at groovy.lang.GroovyShell.evaluate(GroovyShell.java:469)
        at RunScript.runScript(RunScript.java:37)
        at RunScript.main(RunScript.java:18)

Does anyone know why that would be the case and/or a possible workaround?

Regards,
Per




Reply via email to